Week 8 Summaries



Stephen Van Evera, “The Cult of the Offensive and the Origins of the First World War,” in Steven E. Miller, ed., Military Strategy and the Origins of the First World War, Princeton: Princeton University Press, 1984.  pp. 58-107.   

The primary argument that van Evera puts forward in this article is the assertion that the “cult of the offensive” was a principal cause of WWI. The “cult of the offensive”, a phenomenon that was particularly prominent in Europe the decades preceding WWI, is defined by van Evera as the militaries’ tendency to glorify the offensive and adopt offensive military strategies, often accompanied by civilian elite assumptions that the offense had the advantage in warfare. (p.58)

Though based on the resources and technology of the time (machine guns, barbed wire and railroad development)defensive warfare clearly had an advantage over offensive warfare, Europeans lived under a set of political and military myths “which obscured both the defender's advantages and the obstacles an aggressor would confront” (p.59) ‘Attack is the best defense’ was one of the mottos in Germany, whose military glorified the offense and guided the Schlieffen Plan, envisaging attacks on Belgium, France and Russia. Similar bias for the virtues of the offensive—arguably to a lesser extent— was to be found in France, Great Britain, Belgium and Russia. “Mythical or mystical arguments obscured the technical dominion of the defense, giving this faith in the offense aspects of a cult or a mystique...” (p.61) There were mistaken arguments put forward implying that the machine gun actually favored the offense and British and French officers suggested that the superiority of moral on the attacking side overcame superior defensive firepower. In terms of alliances, many Germans believed that ‘bandwagoning’ with a powerful state rather than ‘balancing’ against it was the guiding principle (p.62) and were hoping that Germany's growing strength would get England to opt for neutrality and frighten Belgium into surrender.

According to van Evera, there are five major dangers that may develop when the offense is strong. They were all clearly relevant in the 1914 crisis (p.64-65):
1) States adopt more aggressive foreign policies both to exploit new opportunities and to avert new dangers which appear when the offense is strong.
2)The size of the advantage accruing to the side mobilizing or striking first increases, raising the risk of preemptive war i.e. states mobilize or attack to seize the initiative or deny it to adversaries.
3) Windows of opportunity and vulnerability open wider, forcing faster diplomacy and raising the risk of preventive war.
4) States adopt competitive styles of diplomacy (e.g. presenting opponents with faits accomplis) since the gains promised by such tactics can easily justify the risks they entail.
5) States enforce tighter political and military secrecy, since national security is threatened more directly if enemies win the contest for information.

German expansionism reflected the belief that conquest would be easy both for Germany and for its enemies and that German security required a wider empire, which would be readily attainable either by coercion or conquest. Bandwagon logic fed hopes that British and Belgian opposition to German expansion could be overcome, and the presumed power of the offense on behalf of the Germans made conquest appear both feasible and necessary. A similar mixture of insecurity and perceived opportunity was present throughout Europe. The French feared that the gaining of territory by Austria would affect the general balance of power in Europe and thus harm French interests. Russian policy was motivated by fear that Austrian expansion would undermine Russian security and by hopes that Russia could destroy its enemies.  “In short the belief that conquest was easy and security scarce was an important source of German-Entente conflict. Without it, both sides could have adopted less aggressive and more accommodative policies.” (p.71)

An important question in regards to the 1914 crisis is whether WWI was a preemptive war. According to van Evera, the war was preemptive if Russia and France mobilized preemptively, since these mobilizations spurred German and Austrian mobilization, opening windows for war.  The war was also preemptive if Germany struck Liege preemptively. Three pieces of evidence suggest that important preemptive incentives existed and helped to shape conduct:
        1)      Most European leaders apparently believed that mobilization by either side which was not answered immediately could affect the outcome of war.
        2)      Many assumed that significant mobilization measures and preparations to attack could be kept secret for a brief but significant period.
        3)      Governments carried some mobilization measures in secrecy, suggesting their belief that secret measures were feasible and worthwhile.

None of the European sides allowed for any delay, fearing that the other side would gain the initiative. First-strike advantage was thus considered important, reflecting the implicit assumption that the offense had the advantage.  “Had statesmen understood that in reality the defense had the advantage, they also would have known that the possession of the initiative could not be decisive, and could have conceded it more easily.” (p.75) In addition, secrecy was overvalued. Many officials believed that secret action for a short time was possible. This is why Russian officials apparently lacked confidence in their own ability to detect German or Austrian mobilization and thus decided to mobilize ahead of time so as to forestall surprise preparation by their adversaries. Like their Russian counterparts, French officials also feared that Germany might mobilize in secret. “For their part the Germans apparently did not believe they or their enemies could mobilize secretly, but they did speak in terms suggesting that Germany could surprise the Belgians.” (p.77) The notion of a “window of vulnerability” seems to have also influenced German and Austrian actions. The window of vulnerability logic was in a sense supporting a preemptive strike: ‘Russia is only getting stronger and stronger; we should thus attack now than get crushed later’. Thus WWI was in part a preventive war launched by the Central Powers in belief that they were saving themselves from a worse fate. “The cult of the offensive also helped cause the arms race before 1914 which engendered the uneven rates of military growth that gave rise to visions of windows.” (p.84)

In terms of mobilization, the plans of all sides were characterized by a certain degree of inflexibility.  The scope and character of these plans reflected the assumption that the offense was strong. The cult of the offensive gave planners greater power to bind statesmen to the plans they had prepared, since present plans raised the cost of improvisation if statesmen insisted on adjusting plans at the last minute. A representative example of this is the case of Russia. Russian leaders announced on July 28 1914 that they will partially mobilize against Austria on the 29th.  However, after this announcement, Russian military officers made it clear to civilian leaders that the only options were really between full mobilization or complete retreat since partial mobilization would impede full mobilization.  They opted for the former.  The cult of the offensive made Russian military believe that full mobilization was a safer choice than partial mobilization.  “…the logic of general mobilization in Russia largely reflected and depended upon conclusions deduced from the cult of the offensive, of from its various manifestations. Without the cult of the offensive, a partial southern mobilization would have been the better option for Russia.” (p.89)

Two aspects of the European alliance system fostered the outbreak of war: 1) Both alliances had an unconditional offensive character—allies supported one another unreservedly, regardless of whether their behavior was defensive or provocative.  As a result a local war would tend to spread throughout Europe. 2) German leaders were not convinced that Britain would fight as an Entente member, which encouraged Germany to confront the Entente.  In both cases the cult of the offensive contributed to the problem.
“…the unconditional nature of alliances rather than their mere existence was the true source of their danger in 1914.” (p.97) Indeed, there was a strong assumption in France and Britain that the security of the Entente members was closely interdependent. “These dynamics reflected the general tendency of alliances toward tightness and offensiveness in an offense-dominant world.” (p.100)

The ambiguity of British policy is also often blamed for leading to WWI. The British government is often accused of causing the war by failing to warn Germany that Britain would fight. (p.100) However, British failure to warn Germany was due as much to German secrecy as to British indecision.  Indeed, this culture of secrecy led to a plethora of blunders and accidents. Nevertheless, “the blame for 1914 lies less with the statesmen of the times than with the conditions of the times and the severe demands these placed on statesmen.” (p.103)

Van Evera concludes by reemphasizing that the cult of the offensive was a major underlying case of the war of 1914 that built on a wide range of secondary dangers and led to the involvement of many world powers in the war. “The 1914 case thus supports Robert Jervis and other theorists who propose that an offense dominant world is more dangerous...” (p.106)


Scott D. Sagan, "1914 Revisited: Allies, Offense and Instability," International Security 11:2 (1986), pp. 109-133. (Also in Miller ed., Military Strategy and the Origins of the First World War.)

Sagan reviews the “cult of the offensive” organizational theory argument applied to the events of 1914 and concludes that this approach misrepresents the causes of offensive doctrines, and hence, the underlying causes of war.  Sagan argues that the more fundamental causes of WWI offensive doctrines were the political objectives and alliance commitments of the great powers.  He further concludes that the “cult of the offensive” also misrepresents the consequences of 1914 offensive military doctrines and thus, explicit lessons offered by such analyses for American deterrent strategy are quite misleading.

The origins of WWI remained interesting into the Cold War period for similarities between the events of 1914 and fears about paths by which a nuclear war could begin.  Given perceived incentives to strike first, a relatively small crisis could – through a combination of miscalculation, inadvertent escalation and loss of control over events – spark a tragic and unintended war.  In the case of WWI, elaborate and inflexible war plans met with situational pressures to mobilize and launch offences promptly.  This combination produced a dynamic of escalation and a loss of freedom of action on the part of the political leadership.  But why did the great powers all have offensive military doctrines when the military technology of 1914 (barbed wire, machine guns, railroads, etc.) appeared to favor the defense?  A popular historical explanation is that European militaries and leaders did not update their war strategies with the defensive capabilities demonstrated in the American Civil War and the Russo-Japanese War.  A second explanation (credited to Snyder and Van Evera, et al.) is the “cult of the offensive” where the organizational interests of the professional military are advanced by offensive military doctrines, regardless of whether offensives are recommended by perceived national interests or prevailing technology.

Military bias in favor of the offense
Offensive doctrines 1) enhance the power and size of military organizations because they require larger forces, longer range weapons and more extensive logistic capabilities; 2) tend to prompt military autonomy; 3) enhance the prestige and self-image of military officers; 4) support the “principle of the initiative” or a first-mover advantage; and 5) reinforce military officers’ training that focuses on the possibility of war and viewing the adversary as extremely hostile.

The 1914 Cult of the Offensive
Strategic instability in 1914 was caused not by military technology (which favored the defense and provided no first-strike advantage), but by offensive war plans – these doctrines can be destabilizing even when weapons are not, since doctrine may be more responsive to the organizational needs of the military than to the implications of weapons technology.  Snyder identifies ways in which the organizational interests of the military can affect strategic doctrine, and Van Evera demonstrates the alarming consequences that 1914 offensive plans had on the political leadership’s ability to control events during the July crisis.  In sum, the rapid escalation of the crisis might have been avoided had European leaders recognized the actual power of the defense.

Sagan’s alternative explanation: strategic interests and alliance commitments
Sagan argues that “cult of the offensive” analyses exaggerate the degree to which the offensive doctrines in 1914 were caused by military-motivated biases or misperceptions of the offense/defense balance and hence exaggerate these factors’ role in the origins of WWI.  He cites destabilizing conditions – such as Britain’s failure to present a clear and credible threat of intervention in the July crisis, and the preemptive aspects of Germany’s offensive war plans to immediately capture Liege and to knock France out of the war before Russian mobilization was complete – that more directly led to war.  Sagan identifies three related problems with the “cult of the offensive” explanation: 1) it exaggerates the probability that critical offensive military operations would fail, in particular, it is not persuasive in the case of the Schlieffen Plan; 2) it ignores the fundamental issue of military balances, in terms of both quantity and quality of forces (Sagan believes it doubtful that defenses were so advantageous as to make all states simultaneously secure if they had maintained defensive military doctrines); and 3) it ignores the critical role of the states’ political objectives in determining their military doctrines.

Sagan argues that offensive military doctrines are needed not only by expansionist states, but also by states that have a strong interest in protecting an exposed ally.  This consideration was often recognized in the context of extended deterrence during the Cold War and lay at the heart of the offensive doctrines before WWI.  Sagan does not say that motivated biases due to organizational or psychological factors had no influence in 1914, rather he claims that states’ strategic interests were dominant and the need to support allies was the root cause for the offensive war plans of the great powers.  

Sagan maintains that the alliance system contributed to the dynamic of rapid mobilization that constrained last minute efforts to prevent the outbreak of war.  Furthermore, the “cult of the offensive” theory overlooks the negative consequences that would have resulted had the great powers adopted purely defensive military doctrines.  Defensive doctrines may not produce the same degree of preventive war incentives, but they can undercut deterrence by denying a government sufficient capability to protect its allies.  Thus, maintaining extended deterrence requires some threat of escalation, and as the French discovered when Hitler conquered their allies in 1938-39, purely defensive doctrines can also be strategically destabilizing.


Marc Trachtenberg, “The Coming of the First World War: A Reassessment,” International Security 15:3 (Winter 1990-91).

Many conclusions about the risk of nuclear war stem from theories of inadvertent war, where a crisis triggers a military process of which statesmen loose control, and escalation leads to a war that nobody wants.  Such theories are rooted primarily in interpretations of a single historical episode: the July crisis of 1914 that sparked WWI.   Trachtenberg examines the claim that the military mobilization system played an important role in bringing about WWI.  He argues that theories of inadvertent war are weak in light of historical evidence.

Trachtenberg asserts that if in 1914 everyone understood the system and knew that a Russian or German general mobilization would lead to war, and if, in addition, the political authorities were free agents (i.e. their hands were not being forced by military imperatives or by pressure from the generals) then the existence of a system of interlocking mobilization plans could hardly be said in itself to be a cause of war.  Thus, for an inadvertent theory of war to hold in the July 1914 case, it must be shown either that the implications of mobilization were not understood, (i.e. political leaders failed to understand what their military plans actually meant) or that the political leadership was not free to hold back from war (i.e. the claim that policymakers were stampeded into war in 1914 needs to be tested).

Russian documents show that support for general mobilization was rooted in a belief that war was virtually inevitable, and that at least in the case of mobilizing against Austria, mobilization was pursued for political rather than military reasons.  The Russian leadership understood how risky movement toward mobilization was, and as Benthmann’s warnings show, German statesmen where also aware of the situation.  To hypothesize otherwise ignores the degree to which the Germans had been warned that Britain would intervene in a European war and how Bethmann changed his policy after the announcement of Russian partial mobilization (the Russian decision to order partial mobilization appears to have actually softened of German policy).

On the point of politicians being stampeded into war, Trachtenberg argues that there was no loss of control, only an abdication of control (p.143).  In the German case, Bethmann even made an effort to get the Austrians to pull back.  But after it was determined that war was bound to come eventually, Bethmann resigned to stand by and let it come.  The preventive war argument, which had not been powerful enough to dictate German policy at the beginning of the crisis, now proved decisive.  In the Russian case, the mobilization decision was based on a political assessment: there was diplomatic deadlock and Austria was beginning to move against Serbia, so the issue could no longer be avoided.

Trachtenberg concludes that although preemption was a factor in 1914, its importance is greatly exaggerated in much of the literature.  It is not clear that a nation which mobilizes first has a crucial advantage because mobilizations are difficult to conceal, and if detected quickly, might lead to such counter-mobilizations that there would be scarcely any advantage of moving first.  A decision for general mobilization was quite consciously a decision for war.  And history suggests that leaders did not loose control of military processes but rather used them for political reasons.  The first individuals to propagate the “loss of control” idea were the very people who had the greatest interest in avoiding responsibility for the catastrophe.  After the war, it became apparent that the Germans would never accept a peace settlement based on the notion that they had been responsible for the conflict.  In the interest of reconciliation, the easiest view to take on the origins of the war was that no one had really been responsible for it – the convenient explanation was to blame the alliance structure, the arms race and the military system that had evolved before 1914.  In terms of implications for contemporary politics, Trachtenberg cautions against basing analyses on “myths about the past,” as he believes inadvertent war propositions for the case of WWI turn out to be weak when tested with empirical evidence.


Stephen Van Evera, Causes of War: Power and the Roots of Conflict, Cornell: Cornell Univesity Press, 1999, Ch. 6. (pp. 117-192)

The hypothesis that war is more likely when conquest is easy, i.e. offense-defense theory, is according to van Evera undeveloped, untested and underappreciated.  “Offense-defense theory is the most powerful and useful Realist theory on the causes of war.” (p.117)  The “security dilemma theory” is not quite the same as offense-defense theory since states may also develop offensive capabilities because they have aggressive aims unrelated to their security requirements. According to van Evera, offense dominant means that conquest is fairly easy, while defense dominant that conquest is very difficult. Given that it is never easier to conquer than to defend, offense dominant means that offense is easier than usual.  A developed version of offense-defense theory was first- offered by Jervis in the security dilemma framework. Nevertheless the theory remained controversial and undeveloped. “This chapter outlines, qualifies and tests the hypotheses that Jervis and others proposed, and it suggests and tests new hypotheses.” (p.119)

Van Evera argues that 11 war-causing effects arise when conquest is easy:
1) States pursue opportunistic expansion because such attempts succeed more often and pay greater rewards.
Aggressive states are dissuaded from attacking if the defense is strong and even temperate powers are tempted to attack if offense is strong.
2) States pursue defensive expansion because they feel less secure.  
When conquest is easy states are more expansionist, feeling that their present borders are less defensible and resisting others’ expansion more fiercely. Defensive expansion and strong resistance to expansion stem from the same problem: resources are more cumulative when conquest is easy.  States therefore compete harder to control any assets that confer power seeking wider spheres for themselves while fiercely resisting others’ efforts to expand. Thus, when offense dominates states are cursed with aggressive neighbors. “…states become aggressors because their neighbors are aggressors. This can proceed reciprocally until no state accepts the status quo.” (p.125) Historical examples of this: among others Ancient Athens and Ancient Rome; Russia-Turkey in the Crimean War; 1914 attack of Austria against Serbia; WWI Germany; 1920 Polish attack against the Soviet Union; WWII Germany attacks against Poland and USSR etc.
3) Insecurity drives states to resists others’ expansion more fiercely.
States also resist others’ expansion more strongly in an offense dominant world sharpening conflicts between satisfied and dissatisfied powers (e.g. Israel refused limited Arab territorial demands in the 1950s fearing that such concessions would weaken it.)  States also defend their allies more strongly and unconditionally in an offense-dominant context, fearing that their allies’ demise will spell their own (e.g. Russia and French defense of Serbia in WWI).
4) First move advantages are large creating the risk of preemptive war and other dangers.
a) More territory can be overrun with any material advantage that moving first provides when the offense dominates.
b) The side moving first can disrupt the others mobilization by quickly invading.  
c) Offense dominance leads states to tighten military and political secrecy easing surprise attacks.  
d) Insecure states may compensate for their security by adopting a hair trigger first strike military doctrine.
5) Windows of opportunity and vulnerability are large creating the risk of preventive war. (p.129)
a) A shift in the relative size of national forces causes a larger shift in relative national power when the offense dominates.
b) When the offense dominates, using force offers a more effective remedy for ones’ decline while peaceful buildup is less effective.  
c) Offense dominance fosters secrecy and arms racing.
6) States more often adopt fait accompli diplomatic tactics which often trigger war. (p.131)
When conquest is easy, states adopt more dangerous diplomatic tactics and such tactics are more likely to cause war.  In a fait accompli, the acting side moves without warning and thus cannot retreat without losing face, a situation it hopes to exploit to compel its opponents to concede; but if opponents stand firm collisions are hard to avoid.
7) States negotiate less readily and thus negotiations fail more often. (p.135)
When conquest is easy, states have less faith in agreement because others break them more often.  They bargain harder and concede more grudgingly. Thus states negotiate less often and settle fewer disputes. Cheating in this case pays larger rewards. “As a net result, states negotiate less and let more disputes fester when the offense dominates. This raises the risk of misunderstandings and collisions over small matters, and [the risk] for wars born of misperceptions that survive because the talks that might expose them never occur.” (p.136-7)
8) States enshroud foreign and defense policy in tighter security raising the risk of military miscalculations and political blunders.
“…states compete for information advantage by concealing their foreign policy strategies and their military plans and forces.” (p.137) When the offense dominates, dangers of openness can outweigh advantages driving states to secrecy.  Example: all the European powers enshrouded their policies in dark secrecy during the heyday of the “cult of the offensive” before 1914.  “Secrecy is in turn a Hydra-headed war cause, and the secrecy that offense dominance fosters has a host of war causing effects. Nine bear special mention:” (p.138)
a) Secrecy causes false optimism: states often exaggerate their prospects of victory (e.g. Russia’s false optimism in 1904 Russo-Japanese war.)
b) First move advantages are larger in a more secret world and hence states are more tempted to move first.
c) Secrecy delays states’ reactions to others’ military buildups, hence opening windows of opportunity for the building up state, tempting it to launch preventive war (e.g. WWII Germany.)
d) Secrecy promotes diplomatic fait accomplis.
e) Secrecy causes deterrence failure by causing states to conceal their war plans. Deterrence fails because deterrent threats are made too late.
f) Secrecy can lead states to trigger war unwittingly because they cannot see the hidden tripwires that will spark others’ decisions for war.  
g) Secrecy promotes arms racing causing windows and false optimism.
h) Secrecy inhibits arms control agreements by impeding verification measures.
i) Secrecy narrows the circle of experts consulted on national policy impeding national policy evaluation thus fostering blunders and miscalculations.
9) States react faster and more belligerently to others blunders making blunders more dangerous (p.142)
10) Arms racing is faster and harder to control raising the risk of preventive wars. (p.144)

States have eight incentives to build larger forces when the offense is strong:
a) Resources are more cumulative i.e. wartime gains and losses matter more; gains provide a greater increase in security and losses are less reversible.  
b) Self defense is more difficult because other states’ forces have more inherent offensive capability
c) States are more expectant of war since their neighbors are more aggressive.
d) The early phase of war is more decisive and the possibility of quick victory puts a premium on standing forces.
e) States transfer military resources from defense to offense because the latter is more effective; others then counter-build.
f) States hold military secrets more tightly causing rational overarming and threat inflation on the part of the military for organizationally self serving reasons.
g) States reach fewer arms control agreements when the offense dominates.
h) National militaries have more influence on national perceptions
11) Offense dominance is self-feeding as conquest grows easier states adopt policies that make conquest still easier magnifying the first ten effects
“Offense dominance and defense dominance are self-reinforcing” (p.147)

These are all dangers raised by offense dominance. They also arise when the offense is weak but states think that it dominates i.e. false perception of offensive dominance raises the same dangers as actual offensive dominance.

When Offensive Doctrines and Capabilities Cause Peace (p.152)
“In some hands and under some conditions, offensive capabilities promote peace.” (p.152) For instance, offensive power in the hands of status quo states favors peace by making aggression harder and dissuading aggressors from attacking.  
Additionally, Offensive Doctrines and Capabilities Cause Peace when:
1) The aggressor knows it has provoked the hostility of others.
2) The aggressor knows that the status quo power is benign: status quo powers can wield offensive threats more effectively if they cultivate a reputation for modest aims and restrained behavior.  
3) The offensive force can only attack an attacker: Offensive forces produce more deterrence with less provocation if they can only attack attackers.
4) The aggressor cannot cut the noose: the safest offensive strategies are those that threaten a target state without leaving it able to remove the threat by force. Offensive threats will better deter weaker than stronger states because the weak can seldom cut the noose alone while the strong can more often find a way (e.g. during the Cold War US offensive threats aimed at Sadinista in Nicaragua were bound to produce more compliance than offensive threats aimed at the Soviet Union.)

Causes of Offense and Defense Dominance (p.160)
Military Factors: Military technology, doctrine, force posture and deployments all affect the military offense-defense balance.
1) Technology and doctrine can favor the aggressor or the defender: As 1914 approached the defense was strong thanks to combined effects of lethal small arms, barbed wire, elaborate entrenchments and railroads. During 1919-1945 the power of the offense was restored by motorized armor and an offensive doctrine blitzkrieg for its employment.  This combination overrode machine guns, trenches, railroads and barbed wire. After 1945 thermonuclear weapons restored the power of the defense for good.  
2) Military force posture, deployment and wartime operations: Aggressive operations can corrode key enemy defenses and reckless operations can expose one’s own defenses.
3) Geography: Conquest is harder when geography insulates states from invasion or strangulation, i.e. conquest is hindered when national borders coincide with oceans, lakes, mountains, wide rivers, dense jungles, deserts or other natural barriers that impede offenders.  

Social and Political Order: Popular regimes are generally better at both conquest and self defense than are unpopular regimes but these effects are not equal.  Popularity of regime probably aided offense before 1800 and aided defense since then.  Guerrilla warfare has burgeoned since 1800 partly because the availability of cheap arms has eased the hit and run harassment that characterize guerrilla operations. The defensive power of popular regimes has risen in step with this increase in guerilla warfare.

Diplomatic Factors: Three types of diplomatic phenomena strengthen the defense: collective security systems, defensive alliances and balancing behavior by neutral states.  All three impede conquest by adding allies to the defending side.  

Predictions and Tests of Offense-Defense Theory (p.166)
Offense defense theory makes both prime and explanatory predictions. Prime predictions inferred by the prime hypothesis that “war is more likely when conquest is easy”. Explanatory predictions are inferred from the hypotheses that comprise its eleven explanations.  Tests of these predictions shed light on both whether and how offense dominance causes war.

3 Prime Predictions:
1) War will be more common in periods when conquest is easy or believed to be easy than in other periods.
2) States that have or believe they have large offensive opportunities or defensive vulnerabilities will initiate and fight more wars than other states.  
3) A given state will initiate and fight more wars in periods when it has or believes it has larger offensive opportunities and defensive vulnerabilities.

Three case studies to test these; Europe since 1789 (tests predictions 1 and 2), Ancient China during Spring and Autumn and the Warring States (tests prediction 1) periods and US since 1889 (tests predictions 2 and 3).

3 Explanatory Predictions:
1) Intervening phenomena will be more abundant in periods of real or perceived offense dominance than in other periods.
2) States that have or believe they have large offensive opportunities or defensive vulnerabilities will more often adopt policies that embody intervening phenomena than other states.
3) Evidence should indicate that elites that adopted policies that embodied intervening phenomena did so because they believed that the offense dominated.

Case Studies:

Europe 1789-1990s
The offense defense balance went through 6 phases comprising three up and down oscillations after 1789. Conquest was never easy but markedly easier from 1789-1815, from 1856-1871 and from 1930-1945. Elite perceptions of the offense defense balance mostly parallel these oscillations but not exactly. Tides of expansionism and war loosely correlate with the real offense-defense balance, and more tightly correlate with the perceived offense-defense balance.

Ancient China:
Before 550 BCE defense held upper hand. However, there were 4 subsequent changes that strengthened offense: 1) feudalism declined 2) mass infantry replaced chariots 3) conscription was introduced 4) the creation of huge standing armies. Outcomes of battles and wars reveal the shift towards the offense that resulted from these changes. This increase in the power of the offense coincided with deterioration in international relations; during the Spring and Autumn period (722-481 BCE) interstate relations were fairly peaceful. The subsequent Warring States period (403-221 BCE) was perhaps the bloodiest era in Chinese history.  

US 1789-1990s:
Offense-defense theory predicts that a state such as the US—with a strong economy, and exceptional security endowments— will display average offensive opportunism and less defensive belligerence than other states. The US indeed fits the profile. It has fought other great powers only 3 times (1812, 1917, 1941) and as far as expansionism is concerned, the US has confined itself largely to opportunistic imperialism against frail opponents. Overall, the US has been less bellicose than the average great power;  

Van Evera feels that offense-defense theory passes the test posed in these three cases. He states that though independently none of the three cases provides compelling evidence, all three together make a strong case for the theory.  

How Much History Can Offense Defense Theory Explain?
“The more wars that arise from the search of safety the more wars would have been avoided if states were already safe; hence the more wars are explained by their lack of safety; hence the more wars are explained by offense-defense theory.” (p.185) Examples:
Security fears drove both Athens and Sparta in the Peloponnesian War. Ancient Roman expansion was largely powered by insecurity. The Swedes and French joined the Thirty Years’ War to limit Hapsburg power before it could dominate the Baltic and Europe. Louis XIV triggered war by seizing buffer room to secure France from invasion. Both sides pursued defensive aims in the Crimean war and in the Russo Japanese war;  Austria and Germany sought wider power in 1914 in search for greater security; Poland attacked the Soviet Union in 1920 to bolster Polish security; Nazi German and Imperial Japanese elites argued for imperial expansion largely on national security grounds etc. (p.189)

 Offense-Defense Theory in Perspective:
According to van Evera, offense-defense theory has the attributes of a good theory. It has 1) large importance, 2) wide explanatory range and 3) wide real world applicability. Additionally, it explains an array of war causes—such as expansionism, resistance to expansionism, first move advantage, window of opportunity and vulnerability, faits accomplis, negotiation failure, secrecy, fierce reactions to other’s blunders, arms aces and offense dominance—, causes that were once thought to be independent of one another. (p.122)  


A.F.K. Organski and Jacek Kugler. The War Ledger. Chicago: University of Chicago Press, 1980.  Chapter 1.

Three models have been deployed in order to relate different distributions of power to the coming of war and to tie them to assumptions as to when and why elites choose to fight.

The Balance of Power: When power is more or less equally distributed among great powers, peace will ensue. Conversely, as large asymmetries become discernible in the distribution of power resources, the probability of war increases markedly. According to the theory, the country whose power is increasing will take advantage of its superior power to attack its now weaker adversaries.
The major mechanism through which the balance of power system is maintained is the making and unmaking of alliances. The reason for the dependence on coalitions to change the distribution of power is that the power resources of each system member are viewed as inelastic. A nation can increase its own strength substantially only by adding the strength of allies to its own or decreasing the strength of an adversary by separating it from its allies. Another feature of the balance of power system is it being ultrastable. In maximizing their own power positions, nations group themselves in the kind of balances that tend to keep the system stable, peaceful, and secure. If the equilibrium is disturbed, the system favors adjustments that will return it to equilibrium.

Collective Security: A lopsided distribution of power (with defenders much stronger than aggressor) will support peace; an equal or approximately equal distribution of power will mean war, but the aggressor will be weaker than the coalition. The Assumptions of the model: 1. When a serious international dispute threatens the outbreak of hostilities, the identity of the aggressor will be clear to all. 2. All nations will be equally interested in preventing aggression and will regulate their behavior accordingly. In the balance of power peace is the prized but largely unintended consequence of the way the system works, whereas in a collective security system, peace is the direct and explicit aim of all its members. 3. Like in the balance of power system, alliances are the major method by which the balance of power between aggressive and peaceful nations is to be effected. Yet only in the collective security system the commitment to resist aggression is made a priori.

The power transition: An even distribution of political, economic and military  capabilities between contending groups of nations increases the probability of war; peace is preserved best when there is an imbalance of national capabilities between disadvantaged and advantaged groups; the aggressor will come from a small group of dissatisfied strong countries; it is the weaker, rather the stronger, power that is most likely to be the aggressor. A challenger seeks to establish a new place for himself in the system, a place to which his growing power entitles him. The model argues that source of war is to be found in the differences in size and rates of growth of system members. Most important are economic productivity and the efficiency of the political system in extracting and aggregating human and material resources into pools available for national purposes.

Comparison of the models:

Goals of Elites: Balance of power: Leaders try to maximize power. Strong nations try to expand, potential victims try to protect themselves from aggression. Decision makers in collective security are moved by a rational desire to prevent (or defeat) aggression. Power transition: No general rule to explain elite’s decision to initiate war. It warns that changes in power structure will not, in and of themselves, bring war about. Satisfied great powers will not interpret advantages gained by satisfied lesser powers as a threat. Only if great powers think that the changing system challenges their position, the shifts will be deemed dangerous. General dissatisfaction with the position in the system and a desire to redraft the rules move a country to begin a major war.

The mechanisms that redistribute power: In the balance of power and collective security models changes are the result of alliances. Nations can also arm but the least costly and most certain way to improve power is alliances.  Power transition: The major source of power for a nation is its own socioeconomic and political development. Alliances are not a realistic method of preventing threatening changes in the distribution of power, given the skewness of relations between the great and the lesser nations.

Power Distribution: According to the collective security and power transition models, to preserve peace and security power distribution must be lopsided in favor of the defenders of the system and against the nations that wish to attack it. According to the balance of power model, the recipe for peace is an equal distribution of power between the major sides, because the danger of war increases dramatically when one side begins to gain a substantial advantage over the other. Balance of power predicts that the stronger will attack, collective security posits that the aggressor will be weaker than the coalition, while power transition argues that the attacker will be the weaker party. There is a period during which both dominant and challenger nations are roughly equal in power, and the faster growing power will attack in an attempt to hasten its passage over the dominant country.

The models are tested empirically, and the power transition is found to be best one. Therefore, the source of major war is the differences in rates of growth among the major powers, and of particular importance are the differences in rates of growth between the dominant nation and the challenger that permit the latter to overtake the former in power. The faster one nation overtakes the other, the greater the chances for war.   


Robert Gilpin, War and Change in International Politics, Cambridge: Cambridge University Press, 1981.  Chs 1, 2 (85-105), 4 and 5.  

Chapter 1

Gilpin gives his definitions of the key terms and proposes his theory of political change.  A precondition for political change lies in a disjuncture between the existing system and the redistribution of power in that system.  Equilibrium, or legitimacy, of an international order is defined as “the acceptance of the framework of the international order by all major powers, at least to the extent that no state is so dissatisfied that … it expresses its dissatisfaction in a revolutionary foreign policy.” (12)

The state, defined as “an organization that provides protection and welfare in return for revenue,” (15) faces an indifference curve and seeks to satisfy itself by finding some optimum combination of the twin goals of security and welfare.  The slope of the curve is determined by the specific interests and international environment of a state, and may change due to changes in both internal and external changes.  The curve may even shift in response to changes in the wealth and power of the state, in which case she will demand a larger bundle of security and welfare.  The state has three main foreign policy goals of territorial expansion, prestige enhancement, and maximization of influence over the world economy.

The control over the international system is a function of three factors: (1) the distribution of power among states, or coalitions of states, (2) the hierarchy of prestige (i.e. reputation for power) among states, and (3) a set of rights and rules that govern, or influence the interaction among states.  The perceptions of prestige tend to lag behind changes in power distribution, thereby causing a breakdown in the governance of the system and often leading to armed conflict.  The rules concerning territoriality function as the basic mechanism in the international system, governing the distribution of scarce resources and creating expectations of appropriate behavior.

There are three types of international changes.  First, there is systems change, involving a change in the nature of the actors constituting the system.  Secondly, there is systemic change, a change in the form of control or governance of the system.  And lastly, there is interaction change, a change in regular interaction and processes among the actors.  Change can take place either incrementally or in a revolutionary manner.  What causes the change is “differential rates of change between the international distribution of power and the other components of the system that produces a disjuncture or disequilibrium in the system.” (48)

Chapter 2, pp. 85-105

Gilpin discusses the structure of the international system and the domestic conditions of societies as primary determinants of foreign policy.  He begins with discussion of Waltz’s idea of bipolar stability and raises three cautions.  Both of the great powers may not be vigilant in maintaining the duopolistic balance, can overreact to a minor change, and collusive agreements among the two great powers may well be easier in a bipolar world, but they also break down more easily.  

What drives states to wage war is perceived certainty of gain, which is also a function of power distribution.  The differential growth of power among states alters the cost of changing the international system and thus the incentives for changing it (the law of uneven growth).

The key determinant of domestic source of change is the relationship between private gain and public gain.  In other words, “the necessary condition within a state for it to attempt to change the international system is that domestic social arrangements must ensure that the potential benefits to its members of carrying out this task will exceed the anticipated costs to its members.” (98)  If both are complimentary, then there exists a strong impetus for the state to expand.  To this end, the arrangement of domestic sociopolitical institutions is of great importance, as they channel individual behavior into activities that bring the private rate of return close to the social rate of return.  The primary mechanism for reconciling private and social benefits and costs is society’s definition of property rights.

Chapter 4

Here the author discusses Assumption 4 (see pp. 10-11, and 156), the basic idea of which is that once an equilibrium between the costs and benefits of expansion is reached, the tendency is for the costs of maintaining the status quo to rise faster than the capacity to finance the status quo.  This divergence between costs and the capacity (resources) causes a fiscal crisis for the dominant power(s).  The divergence is due to the fact that the protection and consumption shares of national income to increase, while the investment share decreases.  There are two factors affecting political decline of the dominant state: internal and external.

Internal Factors Affecting Political Decline


•    Structural changes in the economy:  Every economy is subject to the law of diminishing returns, which causes the growth of every society to conform to an S-shaped curve.  Even innovations tend to be subject to the law of industrial growth, that is, the tendency for the growth impulse of any innovation to come to an end.
•    Law of the increasing cost of war: Due to the increased costs of military capabilities and diffusion of military technology, the costs to the dominant state of maintaining the system rise with time.  But the increased effectiveness of modern technologies can moderate the impact.
•    There is the tendency for both private and public consumption to grow faster than the GNP as a society becomes more affluent.
•    Structural change in the character of the economy: service industries tend to have a lower rate of productivity growth than manufactures.  Thus service economies tend to experience declining productivity and economic retardation.
•    Corrupting influence of affluence: This causes divergence in private and public interests as well as makes the people of the dominant state neither concede to the just demands of rising challengers nor make the necessary sacrifices to defend its threatened world.

External Factors Affecting Political Decline


•    Increasing costs of political dominance: Due to both the increasing costs of protecting its sphere of influence and the decreasing profitability of the status quo, the dominant powers over time tend to experience a decline.
•    Loss of economic and technological leadership: The diffusion of economic and military technology to less advanced societies is a key element in the international redistribution of power.  “Backward” economies can make the most of their conditions by adopting the most advanced and most thoroughly proven techniques and thus skip historical stages of development.

Through both internal and external factors stated above, differential rates of growth of declining and rising states in the system produce a decisive redistribution of power and result in disequilibrium in the system.

Chapter 5


This chapter discusses Assumption 5, which states that if the disequilibrium is not resolved, the system will be changed and a new equilibrium will emerge that reflects the redistribution of power.  To maintain the status quo, the dominant power(s) can seek to either increase the resources or reduce its commitments and influence.  The most satisfactory solution is increased efficiency in the use of existing resources, which depends on the society’s capacity to innovate, which in turn depends upon its socio-political and economic institutions.  

The dominant state(s) can also reduce costs by (1) eliminating the reason for the increasing costs, (2) expanding into a more secure and less costly defensive perimeter, and (3) reducing international commitments.  The last method can involve unilateral abandonment of the state’s commitments, seeking rapprochement with less threatening powers, or conceding to the demands of the rising powers.  

If the state of disequilibrium is unresolved peacefully, then a hegemonic war is likely to occur.  The consequence of such war is the change of the system in accordance with the new international distribution of power.  Hegemonic war involves a direct contest between the dominant power(s) and the rising challenger(s) and affects the nature and governance of the system.  There are three preconditions for the outbreak of a hegemonic war.: (1) the “closing in” of space and opportunities for the great powers; (2) psychological factors, the perception that “a fundamental historical change is taking place and the gnawing fear of one or more of the great powers that time is somehow beginning to work against it and that one should settle matters through preemptive war.” (201); and (3) the course of events escaping human control.

Peaceful international change appears to be most feasible when it involves changes in an international system rather than change of an international system.  But a hegemonic war is not the end.  The conclusion of it is the beginning of another cycle of growth, expansion, and eventual decline, and history repeats….


Thucydides, The Peloponnesian War (New York: Norton Critical Edition, 1998), (up to the Pentecontaetia).

I suggest looking at a map to acquaint yourself with the positions of, moving counter-clockwise around the Greek peninsula, Epidamnus (11 o'clock, a coastal city), Corcyra (9 o'clock, an island), Sparta (6'oclock, inland city), Corinth and Athens (3 o'clock, coastal cities), and Potidaea/Pallene (1 o'clock, coastal city). The Peloponnese is the southern area of Greece, with Sparta as its political and geographic center. The required reading details the events leading up to the war between Athens and Sparta. The remainder of the book details the war itself.

Introduction:

"The Spartans occupy two-fifths of the Peloponnese and stand at the head not only of the whole Peloponnese" (Book I, section 10). Previous to the Peloponnesian War, the Greek cities of Athens and Sparta, as well as their Greek allies and colonies had allied against the Persians and defeated them. In the process, Athens was abandoned and destroyed. The people of Athens became a naval power without a strong land base, and Sparta built up its land army. "For a short time the war-time alliance held together, but it was not long before quarrels took place and Athens and Sparta, each with her own allies, were at war with each other, while among the rest of the Hellenes states that had their own differences now joined on or other of the two sides. So from the end of the Persian War till the beginning of the Peloponnesian War, though there were some intervals of peace, on the whole these two Powers were either fighting with each other or putting down revolts among their allies" (I: 18). When the Spartans took Greek cities from the Persians, they installed oligarchies that would work for Spartan interests. The Athenians, however, took over the navies of the conquered cities, turned those cities into colonies, and required that tribute be paid, leaving the Athenians with a massive navy following the war. Thucydides writes that "What made war inevitable was the growth of Athenian power and the fear which this caused in Sparta", and that this history, "human nature being what it is, will, at some time or other and in much the same ways, be repeated in the future" (I, 22-23).

The Dispute Over Epidamnus (435-3 BC):

Epidamnus is a city north of Corcyra that was founded by Corinth (a very wealthy Greek power) and later colonized by Corcyra. Shortly before the war between Athens and Sparta, the democrats lost power relative to the aristocratic party in Epidamnus, and so sent a request for help to Corcyra, which refused the request. In response, and with the support of the Oracle of Delphi, the democrats switched their alliegance to Corinth, from which they asked assistance. The Corinthians "felt they had a good right to do so, since they regarded the colony as belonging just as much to them as to Corcyra; and at the same time they hated the Corcyraeans because they failed to show to Corinth the respect due from a colony to the mother city" (I:25). Corinth sent troops and settlers to Epidamnus to restore the democracy, to which Corcyra reacted by besieging the city.  During the naval siege, Corinth rallied substantial allies and prepared to send a larger naval force to Epidamnus. The Corcyraeans offered to submit the dispute to a nonaligned city to arbitrate. "The Corinthian reply to this was that if Corcyra withdrew the fleet and the foreign army from Epidamnus, then discussion might be profitable; but it was quite absurd to talk of arbitration while the city was still being besieged" (I:28).  Corinth sent 75 ships to battle against 80 Corcyrean ships. The Corcyreans won the naval battle, and on the same day their siege of Epidamnus succeeded. During the battle the Corcyreans destroyed 15 Corinthean ships, and after the battle the took all Corintheans in Epidamnus and in the defeated navy prisoner. Except for the imprisoned Corintheans, all foreigners in Epidamnus were sold as slaves, and all prisoners taken in the naval battle were put to death. Corcyra then proceeded to burn and lay waste to nearby cities allied with Corinth.

The Dispute Over Corcyra (433 BC):

In response to their defeat, Corinth began building ships and increasing the efficiency of its navy. Corinth was allied with Sparta, which in turn had a treaty with Athens. Corcyra, on the other hand, had no allies other than her own colonies, having refused to assist other cities in their time of need. Corcyra decided therefore to ask Athens to be its ally. In the speech to the Athenian assembly, the Corcyreans said, "We used to think that our neutrality was a wise thing, since it prevented us being dragged into danger by other people's policies; now we see it clearly as a slack of foresight and as a source of weakness. . . . you will not be helping aggressors, but people who are the victims of aggression. . . . In case of war we should obviously be useful to you, but some of you may think that there is not immediate danger of war. Those who think along those lines are deceiving themselves; they do not see the facts that Sparta is frightened of you and wants war, that Corinth is your enemy and is also influential at Sparta. Corinth has attacked us first in order to attack you afterwards. She has no wish to make enemies of us both at once and find us standing together against her. What she wants is to get an initial advantage over you in one of two ways -- either by destroying our power or by forcing us to use it in her interests" (I:32-33). The Corcyraeans went on to note that technically, it was not a violation of the Athens-Sparta treaty to ally with Corcyra, a neutral. "What is really monstrous is a situation where Corinth can find sailors for her ships both from her own allies and from the rest of Hellas, including in particular your subjects, while we are shut off from a perfectly legitimate alliance" (I:35). The Corcyraeans added that if Athens did not ally with Corcyra, the would "actually be allowing [Sparta] to build up their strength from the resources of your own empire" (I:35). The Corcyraeans also appealed to their need for an alliance with a strong navy. "Your aim, no doubt, should be, if it were possible, to prevent anyone else having a navy at all: the next best thing is to have on your side the strongest navy that there is [that of Corcyra]" (I:35).

In response to the Corcyraean speech to the Athenian assembly, the Corintheans made a speech based primarily not on the power politics of the region, but on ethical standards and the need for reciprocity in the existing alliance relations. Corcyra was charged with being insubordinate to Corinth, her mother city, and to ignoring Epidamnus during its period of distress. "Every power should have the right to control its own allies . . . You [Athens] were short of warships when you were fighting Aegina . . . Corinth then gave you twenty ships. . . . You may think that Corinth will be your enemy in the future, but it is not worth your while to be carried away by this idea and to make open enemies of us now. . . . you will find that an act of kindness done at the right moment has a power to dispel old grievances" (I:40-42).

Athens at first decided to support Corinth, but then at a second assembly allied with Corcyra. Thucydides writes, "The general belief was that, whatever happened, war with the Peloponnese was bound to come. Athens had no wish to see the strong navy of Corcyra pass into the hands of Corinth.  At the same time she was not averse from letting the two Powers weaken each other by fighting together; since in this way, if war did come, Athens herself would be stronger in relation to Corinth and to the other naval Powers. Then, too, it was a fact that Corcyra lay very conveniently on the coastal route to Italy and Sicily" (I:44). Athens sent 10 ships which were added to the 110 Corcyraean ships. The Corinthians sent 150 ships. The Corintheans won the first battle, and killed rather than took prisoners. The next day 20 more Athenian ships arrived to support the Corcyraeans, and fearing the start of a wider war with Athens, the Corintheans withdrew. Both Corinth and Corcyra declared victory. "This gave Corinth her first cause for war against Athens, the reason being that Athens had fought against her with Corcyra although the peace treaty was still in force" (I:55).

The Dispute Over Potidaea

The next contribution to the breaking out of war between Athens and the Peloponnese was the dispute over Potidaea. The Potidaeans were colonists of Corinth but also tribute-paying allies of Athens. After the Corcyra dispute, Athens demanded of Potidaea that it remove its fortifications, send hostages to Athens, and expel all resident Corintheans. "These demands were made because Athens feared that, under the influence of Perdiccas and of the Corintheans, Potidaea might be induced to revolt and might draw into the revolt the other allied cities in the Thracian area" (I:56). In response Potidaea revolted and allied with Corinth and Sparta, who promised to attack Attica if the Athenians attacked Potidaea. Athens sent 30 ships and 1000 troops to Potidaea to enforce their previous demand, and another 40 ships and 2000 troops to other cities in revolt.  Corinth sent 2000 troops to protect Potidaea. Though they did not breach the walls of Potidaea, the Athenians won the naval and land battles, and ravaged the countryside.

The Debate at Sparta and Declaration of War
In response to the second defeat of Corinth, that city called an assembly at Sparta in order to advocate war against Athens. In addition to the grievances above, in particular Athens' interference in Peloponnesian allies and colonies, the Peloponnesian city of Megara pointed out that contrary to the terms of the treaty with Athens, Megara was excluded from all the ports in the Athenian empire and from the market of Athens itself.  The Corinthean delegate spoke last at the assembly, saying "You can see yourselves how Athens has deprived some states of their freedom and is scheming to do the same thing for others, especially among our own allies, and that she herself has for a long time been preparing for the eventuality of war. Why otherwise should she have forcibly taken over from us the control of Corcyra? Why is she besieging Potidaea? Potidaea is the best possible base for any campaign in Thrace, and Corcyra might have contributed a very large fleet to the Peloponnesian League" (I:68). The Corintheans added, "Do not force the rest of us in despair to join a different alliance" (I:71).

The Athenians noted that they obtained their empire primarily as a result of their victories against the Persians, victories in which the Spartans played only a lesser role. The Athenians claimed that they produced most of the ships, and "provided the most intelligent generals" (I:74). The Spartans, on the other hand, behaved dishonorably. Charged the Athenians, "when you sent out your forces you feared for yourselves much more than for us (at all events, you never put in an appearance until we had lost everything)" (I: 74). In their speech they said, "It was the actual course of events which first compelled us to increase our power to its present extent: fear of Persia was our chief motive, though afterwards we thought, too, of our own honour and our own interest. Finally there came a time when we were surrounded by enemies, when we had already crushed some revolts, when you had lost the friendly feelings that you used to have for us and had turned against us and begun to arouse our suspicion: at this point it was clearly no longer safe for use to risk letting our empire go, especially as any allies that left us would go over to you" (I:75). The Athenians ended, finally, with an ominous warning that war brings nothing more than the unexpected, and that Sparta should carefully consider before entering into this course of events. War would, however, be in the history of Athens and Sparta.


Dale Copeland, The Origins of Major War. Ithaca: Cornell University Press (2001), Chapters 1-4.

Copeland claims the three main realist theories (classical, neoclassical, and hegemonic stability theory) cannot explain the origins of major wars, which he defines as wars in which: (i) all great powers are involved; (ii) there is a high-intensity, ‘all-out’ conflict; and (iii) there is the ‘strong possibility that one or more of the contending great powers could be eliminated as sovereign states’.  In their place he posits a ‘dynamic differentials theory’ that synthesises the strengths of these approaches and ‘brings together power differentials, polarity, and declining power trends into one cohesive logic’.  He predicts that major wars are begun by ‘dominant military powers that fear significant decline’, though systemic considerations like polarity and power differentials, and a more detailed breakdown of types of decline, are further necessary to explain why such powers choose policies that vary from ‘soft-line’ to ‘hard-line’, and ultimately to initiating a major war.

In Chapter 1, Copeland describes the weaknesses of the three main realist theories.  Classical realism predicts that major wars result when the balance of power is disrupted by a preponderant power, but cannot explain cases when war has broken out despite bipolar equality or multipolar systems with close alliances against the potential hegemon.  Neorealism’s focus on polarity is not dynamic enough and cannot explain why a either a multipolar or a bipolar system might move from peace to  war.  Hegemonic stability theory is dynamic (war results when a rising state comes close to equalling the power of a declining hegemon) but lacks a logical reason for why a rising state should attack while it is still rising, since waiting would increase its power.  Moreover its exclusive focus on the two most powerful states of a system makes little sense in a multipolar system.

Copeland’s ‘dynamic differential’ theory makes three main claims.  First, a dominant power perceiving itself to be in decline is the most likely to initiate a major war.  However, states are constrained by the polarity of the system: In a multipolar system, the declining dominant power is more likely to initiate a preventive war (or take ‘hard-line’ actions that increase the risk of one breaking out) only if it has great military superiority over other individual powers, whereas in a bipolar system, the same outcome is likely even if the declining state is merely equal or even second to the rising power.  Finally, Copeland stresses that the declining state’s perception of the depth and inevitability of decline weighs into the probability of attack – thus he breaks down power into military, economic, and potential, and argues that perceived decline in the latter two types is especially crucial in this respect. 

This theory is elaborated in Chapter 2 as a decision-theoretic model that Copeland describes as an attempt to integrate the spiral model or strategic dilemma analysis into the traditional realist theories of major war.  Assuming a state acts according to rational security-maximizing preferences (as opposed to unit-level motives that he does not deny but predicts will be less salient), Copeland argues that the more severe a dominant state perceives its decline to be, the more likely it is to accept the risks of spiraling and take a ‘hard-line’ policy.  He then traces such hard-line policies through five pathways to major war: direct initiation of major war for preventive reasons; direct initiation of major war for ‘aggressive unit-level motives’; crisis provocation to coerce concessions that could ameliorate decline; war through pre-emption; and war through over-commitment of reputations.  (The last two represent pathways to inadvertent war.)

Chapters 3 and 4 form a case study of German decision-making leading up to the July crisis that in turn led to the outbreak of World War 1.  Copeland’s theory predicits that major war in a multipolar system is only likely when one state possesses significantly greater military power and perceives itself to be in deep and inevitable decline.  Such a state is especially likely to provoke a crisis if it has just peaked in relative military superiority, in order to ameliorate its anticipated decline.  Copeland claims that the German decision-making process leading up to July 1914 bears out his predictions more than spiral models, as well as domestic-level theories of internal class struggle or imperial ideologies.  He argues that the war was not inadvertant, or the product of ideology, but that German concern for the enormous long-term growth potential of the Russian Empire led its government to prefer and actively to initiate a preventive war that would prevent Russia from getting stronger.  Thus, Copeland argues, Germany sought to manipulate the diplomatic process and the military constraints to ensure that a major war would ensue with popular support, under conditions as favorable as possible (including having Russia blamed for the onset of the war).  Since Germany pursued this policy despite the grave risk of domestic instability, Copeland concludes that the pressures of relative decline in the international system trumped domestic factors, which favored peace.


Robert Powell, In the Shadow of Power. Princeton: Princeton University Press, 1999.  Chapter 4.  

Uneven rates of growth and development eventually result in changes in the distribution of power, which may lead to disparities between the distributions of power and benefits.  As a result, we can expect to see conflict between rising and declining powers, perhaps to the level of war.  By employing a simple bargaining model, this chapter analyzes how states cope with the threats arising from a shift in the distribution of power.  Here Powell adds to the model in chapter 3 the ability to account for a changing distribution of power.  Two important cases are considered – one of complete information and the other with asymmetric information – each for which states’ equilibrium strategies are derived.  These strategies are then used to examine the relative danger of war during power transitions and whether faster shifts in power are more dangerous.

For a declining state D and rising state R, Powell’s model considers several variables at a time (round of the game) t: the probability that the rising state prevails in war, p; the distribution of benefits, x; the distribution of territory, q; a state’s concerns about future payoffs represented by a discount factor, δ; and the rising and declining states’ cost of fighting, r and d respectively.  See figures on pages 121, 126 and 137.

Note some important assumptions: states are assumed to have a common discount factor and to be risk neutral or averse (p.121); in the asymmetric case, the declining state is assumed to prefer making concessions to launching a preventive war (p.133) and only the declining state is unsure of the rising state’s willingness to use force (p.134); and the distribution of power is assumed to shift for reasons which are exogenous to the analysis (e.g. uneven rates of economic growth not formalized in the model, p.123).  This final assumption precludes the case where a state’s current power depends on resources that it has acquired or given away in the past.  For an analysis of this situation, see Fearon (1996).

If information is complete, the declining state knows how much it has to concede to the rising state in order to satisfy the latter’s minimal demands.  The declining state can either appease the rising state by making sufficient concessions or go to war.  The declining state prefers appeasement to war if it has a large stake in the initial distribution of benefits and if the distribution of power does not shift too rapidly.  Under these circumstances, the distribution of benefits adjusts to reflect the changing distribution of power, and the shift in power passes without war.  On the other hand, if the declining state has a small stake in the status quo or if the distribution is expected to change quickly, the declining state prefers a fight and attacks in the early phase of the shift in power.  A rapid shift in the distribution of power thus creates a commitment problem that results in preventive war even though both states would be better off if they could commit themselves to not using force to alter the status quo; see Fearon (1993).

Asymmetric information creates a risk-return trade off: unsure of the rising state’s willingness to use force, the declining state is uncertain of what it has to concede to appease the rising state to avert or delay war.  How the rising state responds to concessions depends on its willingness to flight.  The declining state only knows that the more it offers, the more likely it is to satisfy its adversary’s demands and the less likely war becomes; however, larger offers also mean having less if they are accepted.  The declining state resolves this trade off by making a series of concessions to the rising state.  Concessions are large enough to satisfy the rising state’s minimal demands if that state is relatively unwilling to use force, and the status quo is revised in favor of the rising state (historical example: Britain and the US in early 19c).  If, however, the rising state is relatively willing to use force, the declining state’s concessions are too small to appease the rising state and war results.  The more resolute the rising state, the earlier the fighting starts. 

Powell’s analysis shows that (contrary to the claims of the power-transition school), power transitions – when the rising state catches up with the declining state and the two are roughly equal in power – are not the most dangerous phase of a shift in the distribution of power.  Moreover, Powell’s model demonstrates that faster shifts are no more dangerous than slower shifts.  However, Powell argues, changes in the technology of coercion that make fighting more costly do make shifts in power less likely to break down in war. 


Randall L. Schweller, "Domestic Structure and Preventive War: Are Democracies More Pacific?" World Politics 44:2 (1992, pp. 235-69.

The article examines how domestic political structures (e.g., a democratic regime) affect the initiation preventive war in cases involving an ongoing power shift. In other words, it offers an explanation (that is based on the nature of the domestic structures) as to why some power shifts result in preventive war while others do not. The broader puzzle that Schweller addresses is whether democratic states are more pacific than non-democratic states. He believes that the existing literature, which aimed to address this puzzle, did not adequately specify the dependent variable (i.e. the type of war), the causal links, and did not hold constant other variables that could influence the involvement in war (e.g., a power shift). Accordingly, he offers a partial, but important, explanation to two questions: Are democracies less prone to get involved in a conflict? And, how do states react to a decline in their relative power?     

Preventive war is defined as a war that is “motivated by the fear that one’s military power and potential are declining relative to that of a rising adversary… states wage preventive wars for either offensive or defensive reasons: to take advantage of a closing window of opportunity or to prevent the opening of a window of vulnerability.”

Although the historical evidence suggests that democratic states are not less likely to be involved in war in general, Schweller’s contention is that “only non-democratic regimes wage preventive wars against rising opponents.” In contrast, when the declining state is democratic it will attempt to form counter-alliances, if the challenging state is non-democratic, and will prefer a policy of accommodation, when the challenging state is democratic. To reiterate one implication of his hypothesis, Schweller contends that a power transition involving a non-democratic state is a necessary but not sufficient condition for preventive war.

To provide a broad explanation to the above contention, Schweller offers a causal account that relies on the adverse effect of liberal public opinion on the willingness of democratic leaders to indulge in preventive action. The “liberal complaisance” of democratic states means that the public mood is willing to support bold action only in response to great anger or great fright. That means that the logic of preventive action, that implies initiating war now to avoid future risks, is peculiar for a democratic audience.  And since a large-scale war is expected to entail heavy political costs, decision-making elites will be reluctant to initiate a preventive war against strong opponents (an exception to that is the case of weak opponents: since strong opposition will not necessarily occur, such wars might take place). In addition, the institutional heritage of openness and division of power, which are generated by the democratic public opinion, inhibit the preventive motivation for war. The explanation to that is that the military’s offensive inclinations are curbed by a supervising civilian regime. Moreover, the prevailing enlightened liberal-moral-values (e.g., individual liberty and pursuit of happiness) prevent the initiation of predatory or offensive preventive wars (i.e. wars with aims such as national glory, economic gain, or territorial acquisition). As opposed to preventive wars, pre-emptive wars, which occur in reaction to an imminent and immediate danger, are morally acceptable in the eyes of a liberal-democratic public opinion.            

To explain the specific prediction of his theory, Schweller suggests that: (1) Democracies will accommodate a democratic challenger because they view their relationships with other democratic states in positive-sum, rather than zero-sum, terms. (2) Democracies will balance, rather than prevent, a non-democratic challenger (unless they feel that the outcome is certain and not costly) because they will not want to alienate their democratic allies. (3) Non-democratic states will wage a preventive war against democratic and non-democratic challengers due to “the combination of militarization of society, glorification of national power, amoral and technically rational approach to politics, and centralized authority.” These characteristics will also tend to alarm the neighbors of such states and thus heighten the motivation for preventive war, which authoritarian neighbors may contemplate.    

To test the theory, the author examines a database of all great power preventive wars since 1665. Apparently, the model’s predictions were strongly confirmed by the data. In addition, three case studies were surveyed in more detail to examine and demonstrate the theory’s causal explanations.

To conclude, the author employs the theory to make predictions about the outcome of current events (e.g., he believes that the pacific Russian reaction to the rise of German power in the beginning of the 1990’s emanates from, and its continuation depends on, its democratization processes) and of “emerging” power shifts (i.e. he predicts that the US will respond with peaceful accommodation the expected rise of Japan…). Another relevant future prediction that the author offers is that although significant global power shifts are underway, we can expect a peaceful change due to the increase in the number of democracies in the world (and due to the rapid spread of liberal values).  


Barry R. Posen, “The Security Dilemma and Ethnic Conflict”, Survival 35:1, pp. 27-47.

In this work, Posen attempts to explain the occurrence of ethnic conflict by using a basic concept from the realist paradigm in international relations—“the security dilemma”. More specifically, Posen looks at the factors that can create an intense security dilemma after the break up of an imperial order, when groups are faced with the task to provide for their own security. Posen equates the collapse of an imperial regime (e.g. the Soviet Union) with “emerging anarchy” (p.103) and contends that the groups emerging from the collapse of this imperial order would have the quest for security as their primary concern. In their competition for security, groups amass more power than needed for their security and thus start posing a threat to others. Posen contends that in this state of emerging anarchy, offensive and defensive capabilities become indistinguishable, making the offense superior to the defense; this situation clearly signals the presence of an intense ethnic security dilemma. 

Posen contends that groups assess each other’s offensive military capabilities in terms of cohesion and past military record. “The nature of military technology and organization is usually taken to be the main factor affecting the distinguishability of offense and defense.”  (p.105) However, such distinctions are hard to make.  A key element of combat power of armies that can be deemed of an offensive nature is the cohesion and strength of the group’s national identity.  “The groupness of the ethnic, religious, cultural, and linguistic collectivities that emerge from collapsed empires gives each of them an inherent offensive military power.” (p.106) Given that the military capabilities of the ethnic groups tend to be rather rudimentary, their offensive will be stronger the more cohesive their sponsoring groups appear to be.  “In sum, the military capability of groups will often be dependent on their cohesion, rather than their meager military assets.”(p.107)

In terms of the superiority of offensive over defensive action, Posen discusses the role of technology and geography.  As far as technology is concerned, if a group inherits a nuclear deterrent and its neighbors do as well, “groupness” is not likely to affect the security dilemma with as much intensity as in non-nuclear cases. “Because group solidarity would not contribute to the ability of either side to mount a counterforce nuclear attack, nationalism is less important from a military standpoint in a nuclear relationship.” (p.108) Geography and settlement patterns can also give an advantage to offense over defense, with the presence of isolated ethnic groups giving rise to incentives for preventive war. After the collapse of central authority, groups find themselves compelled to make calculations of their relative power. Due to the complexity of the situation many of the groups believe that their prospects of war are better earlier rather than later and thus groups are tempted to proceed with preventive military actions. 

Posen then proceeds to outline two case-studies to prove his argument: Croats-Serbs and Russia-Ukraine. In the case of Croats and Serbs, each group identified the reemerging identity of the other as an offensive threat. Settlement wise, Serbs were scattered in vulnerable islands and could only be rescued by offensive action from Serbia. Additionally, as Croatia achieved international recognition, its military power was expected to grow. Therefore from the Serbian perspective, Serbs in Croatia were insecure and expected to become more so.  “Preventive war incentives were consequently high” (p.112) The case of Russia and Ukraine is quite different from the Yugoslav case: “A principal stabilizing factor here is the presence of former Soviet nuclear forces in both Russia and Ukraine, which provides each republic with a powerful deterrent.” (p.114) Each side perceives of the other’s “groupness” in rather benign terms and settlement patterns do not create pressure for offensive action.  The history of relations between Russia and Ukraine is according to Posen conducive to peace. In sum, “in Yugoslavia Croats and Serbs found each other’s identity a threat because of the primitive military capabilities they could field and the terrible record of their historical relationship. In the Russia Ukraine case, nuclear weapons mute the conventional competition, making group cohesion less of a military asset.” (p.118)

Posen ends his discussion by highlighting his three (far-sweeping) conclusions (p.119):
1) The security dilemma and realist international relations theory have considerable ability to explain and predict the probability and intensity of military conflict among groups emerging from the wreckage of empires.
2) The security dilemma suggests that the risks associated with these conflicts are quite high. 
3) If outsiders wish to understand and reduce the odds of conflict, they must assess the local groups’ strategic view of their situation.


James D. Fearon, “Commitment Problems and the Spread of Ethnic Conflict”, in D.A. Lake and D. Rothchild eds., The International Spread of Ethnic Conflict, Princeton University Press (1998).

Fearon’s article develops two main arguments:

1) It analyzes why the upsurge of ethnic conflict observed in Eastern Europe and the former Soviet Union will be self-contained and unlikely to involve and polarize major powers and explains why—even though these conflicts are containable— major powers have humanitarian, economic and ideological incentives to understand and prevent them.

2) It suggests that the causes behind the resurgence of ethnic violence in the former communist countries result from commitment problems. The assertion is that in post-Soviet Eastern Europe, where there is no third party that can credibly guarantee agreements, ethnic majorities are unable to commit themselves not to exploit ethnic minorities in a new state.  Regardless of what ethnic majority leaders commit to now, there is no guarantee that they will not renege on their promise in the future.  Given this expectation, fighting now in hopes of secession from a weak, newly formed state might seem as a better alternative for the minority. (p.109)

In terms of his first argument, i.e. that ethnic conflicts of the kind observed in Eastern Europe are self-limiting, Fearon contends that since these conflicts are about secession and self determination, their claims will only extend so far as to include brethren of non-negligible presence in the vicinity. Major powers are thus not seriously threatened by this for two main reasons: 1) thanks to the nuclear revolution, powers are far less dependent on allies than they were before; “the alliance preferences of minor powers simply do not matter as much as they did in the non-nuclear past.” (p.110) and  2) “…for the most part ethnic conflicts are particularist rather than universalist” (p.111) While the Cold War was not simply about geopolitics but also about ideology, “ethnic conflicts cannot be a struggle for hearts and minds since ethnic identity is presumed to be ascriptive.”(p.111)

Fearon then proceeds with his discussion of the commitment problem using the example of the conflict between the Serb minority and Croat majority in Croatia in 1991.  The rapid polarization of Serbs and Croats in Croatia— which is inconsistent with an “ancient hatreds” explanation, according to which there would be widespread hostility waiting to erupt at any time—is explained by a commitment problem operating between the majority Croats and the minority Serbs in Croatia. “With the declaration of independence, Serbs in Croatia whether extremist or utterly indifferent to such things, faced the prospect of entering the new state of Croatia with no credible guarantees on their political status, or economic and even physical security…Faced with this prospect, it would make sense for even nonextremists Serbs to try to fight now rather than later, despite the costs of civil war and the existence of bargains that majorities on both sides might have preferred.” (p.115)  

In an attempt to make his argument more precise, Fearon uses a simple game model of the problem faced by a majority and minority ethnic group after the disintegration of an “imperial” authority previously over both of them. One of the main underlying assumptions of the game is that it will be more difficult for the minority to secede after the majority has consolidated its control of the new state and begun to build up its security apparatus. The solution to the model he specifies is a subgame perfect Nash equilibrium. Backwards induction suggests that as long as the minority group would prefer fighting in the first period to receiving none of the benefits in the new state, then it will strictly prefer to fight for secession in the first period. “Costly ethnic war is thus explained as the result of the majority’s inability to make a credible commitment to the minority.” (p.118) 

Fearon also briefly discusses the differences between the ethnic security dilemma argument put forward by Posen and his discussion of the commitment problem. In Posen’s work, preventive war becomes likely as a result of interspersed settlement patterns, which in turn create offensive advantages, making it possible for many competing groups to assume that their prospects in war would be better earlier than later.  In Fearon’s case preventive wars arise as a result of the majority’s inability to credibly commit to the minority rather than to mutual miscalculations of relative power. Additionally, the security dilemma is typically assumed to explain how anarchy can lead to a war between security-seeking actors who have no aggressive or revisionist desires. The commitment problem on the other hand assumes that there must be some set of substantive issues over which the minority and majority have conflicting preferences.  “Otherwise the minority has nothing to fear concerning what policies the majority will implement in the new state and the fact of anarchy is then inconsequential.” Lastly, the commitment problem gives an explicit answer to why groups in conflict cannot reach a settlement but rather have to go to war, while the security dilemma does not, leaving the issue of why signaling could not be sued to reduce uncertainty unaddressed.(p.121)

Fearon then proceeds to discuss certain factors that affect the severity of the commitment problem:
1) Military strength and cultural preferences of the minority: The commitment problem does not operate if fighting now is worse for the minority than the worst situation they would face in the future. 
2) Settlement patterns of minority and majority groups: “When populations are highly intermixed, to “secede” means to fight and we should expect war by the logic of the model.” (p.122); in Posen’s account by contrast, interspersed populations are more prone to violence because of greater offensive advantage.
3) Presence of external guarantors or ethnic brethren in neighboring states who are both willing and able to threaten credibly to intervene on behalf of the minority if they are abused: The commitment problem can be eliminated if there is some powerful third party willing and able to commit to intervene if the majority does not respect political commitments to the minority. 
4) The extent of the minority’s expected decline in ability to secede in the future.
5) The value of “exit” for individuals in the minority group and the social and political organization of the minority. (e.g. urban dwellers would do better by exiting than rural farmers.)