Week 9 Summaries



Karl Deutsch and J. David Singer, “Multipolar Power Systems and International Stability,” World Politics 16:3 (1964), pp. 390-406.

The authors seek to examine the relationship between multipolarity and international stability.  Their argument is that due to interaction opportunity, the increasing number of independent actors increases the stability of the international system.  Stability is defined as the “probability that the system retains all of its essential characteristics, [so that] no single nation becomes dominant, most of its members continue to survive, and large-scale war does not occur.” (390)  An arms race is defined as conflict in which “the rival states stimulate one another to divert increasing proportions of their national income to military preparations.” (391, original emphasis)  

There are two mechanisms at work.  On the one hand, an increase in the number of independent actors in the system increases interaction opportunities, which in turn generates cross-pressures to inhibit social cleavages and enhance social stability.  In a system characterized by conflict-generating scarcities such as the international system, each and every increase in opportunities for cooperation will diminish the tendency to pursue a conflict.  This is so because the more nations there are, the greater will be the number and diversity of trade-offs available to the total system, making the possibility for compensatory and stabilizing interactions more likely to occur.  

On the other hand, an increase in the number of independent actors reduces the share of attention (information-processing and resource-allocating capabilities) that any one state can devote to any other.  Given that there has to be a minimum level of attention in order for a conflict to escalate, the increase in number of independent actors is likely to have a stabilizing effect upon the system.

Moreover, assuming that a country’s response to an increase in the arms expenditure of a rival is proportional to that part of the increment in the rival’s armament, the arms race would tend to be slower under multipolar conditions than under bipolar ones, since the more great powers there are, the less increase there has to be in one’s military expenditure in order to balance the increase in the rival’s arms expenditure.

The authors, however, also make the point that if domestic regimes are unstable, then an increase in the number of independent actors may not be conducive to international stability.  Furthermore, in the long run, the multipolarity is unstable because (1) it does not provide the possibility for the creation of new states, and hence predicts an eventual bipolar world or the survival of a single power; and (2) the balance-of-power world produces eventually dramatic and catastrophic changes.  But in the short and middle runs, a mutilpolar world is more stable than a bipolar one.


Ted Hopf, “Polarity, the Offence-Defense Balance, and War,” American Political Science Review 85:2 (1991), pp.  475-493.

Waltz argues that a bipolar system is more stable than a multipolar system, stability defined as change in the number of poles. He also defines stability as the avoidance of great power war. Allies are considered an intervening variable between polarity and instability. Alliance strategies in a bipolar system have a benign effect on systemic stability, while under multipolarity such strategies lead to wars involving the poles.

The author claims that instability is explained by a comprehensive definition of offense-defense balance. He defines instability using four measures: frequency of wars; duration of wars; their magnitude (= number of poles involved), and severity (= battle deaths per war year in proportion to population).  The offense-defense balance consists of three elements:

1. Technical offense-defense military balance - Offensive and defensive advantages should be separated to tactical and strategic categories. Tactical offensive advantage is the ability to seize a piece of an enemy’s territory at less cost to oneself than it requires for the defender to protect or retrieve it. A strategic offensive advantage is the ability to seize and/or occupy as much of an enemy’s territory as is necessary to destroy its military potential at less cost to oneself than is required for the defender to protect its territory or retake it. In the case of both tactical and strategic offensive advantage we should expect frequent wars, but they will be short with high casualties. There should be a greater incidence of interpolar wars, given the enormous promised gains from victory.
Where there is an advantage for the strategic offensive but a tactical defensive advantage, wars will still be frequent, given the enormous gains of conquest, but not as in the former, doubly offensive case. Wars will be longer and casualties more severe than in the previous case. The prospect of high gains will inhere again to greater interpolar warfare. In the case of strategic defensive advantage and tactical offensive advantage wars will be frequent due to the ability to seize and hold territory, but not as frequent as the first two cases. Wars should be short and casualties low due to the relative ease of attaining limited territorial gains. Interpolar wars should be less frequent, given the lack of prospective strategic gains from wars.
 Where there is both strategic and tactical advantage, wars will be infrequent. Wars that do occur will be short and casualties low. There will be still fewer cases of interpolar war than in the previous case.  

2. Cumulativity of power resources – includes both the availability and the extractability of power resources. Available power resources are the material elements that constitute military and economic power in a given historical period.  For instance, if Germany were to consider an attack on another state in the 19th century is would consider the grain, coal, iron ore and other industrial endowments of that state, but not its uranium. The greater the relevance of another state’s resources to increasing one’s own power, the greater the incentive to go to war.
The extractive power of the potential conquerer includes the relative ease of occupation or administration and the relative ability to transfer whatever power resources are available to the conquering state. The lower the costs of occupation the greater the instability in the system.

3. Strategic beliefs – Offensive strategic beliefs assume rules to be very concerned that if they allow another pole to gain military victory anywhere, these opposing rulers will learn three lessons that will redound to the disadvantage of the defeated state: a. the victorious rulers will believe they can successfully challenge the recently defeated state even in areas of the globe that are strategically vital to the defending state. B. the defending state’s allies will begin to question the advisability of relying on the former’s security arrangements. c. states will fall like dominoes into to the lap of the aggressor instead of balancing against it.
Defensive beliefs mean that rulers are unconcerned about credibility, confident that allies will balance and dominoes will not fall after their adversary’s victories.   

The argument is tested with regard to 16th century Europe. The European system was multipolar from 1495 to 1521. England, France, Habsburg Austria/Germany, Spain, Venice and the Ottoman empire had relatively equal military power. From 1521 to 1559 the European system was bipolar (the Habsburg and Ottoman empires).
The offense-defense balance predicts a significant amount of instability in the first period due to tactical offensive military advantages (artillery); available power resources (money could be acquired by taxing the defeated population and then converted to military power); and offensive strategic beliefs (fears of falling dominoes and bandwagoning  allies). But this instability should be mitigated by the strategic defensive advantage (mercenary armies often refused to fight after being refused pay increases; lengthy sieges on fortified towns drained state treasuries). In addition, brutal occupation policies by the conquerer made resources extraction very problematic. Waltz’s theory of polarity will simply predict greater instability in the first period than in the subsequent bipolar period.  

In the second, bipolar, period the offense-defense balance would not predict any significant change from the multipolar period. This period is one of strategic defensive dominance and growing tactical defensive advantage but also one where power resources are available and extracted with increasing ease. In addition, offensive strategic beliefs are the norm. Waltz would predict much more stability in this bipolar world.
The data support the offense-defense theory and contradict the polarity theory. An analysis of the frequency, length and magnitude of wars in both periods shows that the system became only marginally more stable after the shift from multipolartiy to bipolarity.
Waltz’s arguments about alliances are also contradicted. He argues that in multipolarity, due to uncertainty and relative equality in military capabilities, great powers will pass the buck, allowing a challenger for hegemony to succeed. There will also be frequent great powers wars due to rigid strategies adopted by poles solicitous for their allies’ concerns. Yet the great powers in fact did not pass the buck. They balanced against the state that seemed most threatening. The balancing strategies were optimal, neither buckpassing nor chainganging  (= too tight alliances).      

Stephen M. Walt, Origins of Alliances.  Ithaca: Cornell University Press, 1987.  Chapters 1, 2, 5.  

Chapter 1
This book answers questions like: What causes states to support one another’s foreign policy or territorial integrity? How do statesmen choose among potential threats when seeking external support? How do great powers choose which states to protect, and how do weaker states decide whose protection to accept?  How do states choose their friends?

An alliance is defined as “a formal or informal relationship of security cooperation between two or more sovereign states.  This definition assumes some level of commitment and an exchange of benefits for both parties; severing the relationship or failing to honor the agreement would presumably cost something, even if it were compensated in other ways.”  A state’s grand strategy is a theory explaining how it can “cause” security for itself: if we do A, B, and C, the desired results X, Y, and Z will follow.   

The Cold War between the US and USSR was a competition for allies.  Throughout the Cold War, US has policy reflected the belief that states most often ally to appease a threatening power, and pactomania was the logical result.  US opposition to leftist and Marxist movements reflect the belief that states with similar internal characteristics are likely to ally.

The book argues that: (1) balancing is far more common that bandwagoning, but in contrast to traditional balance of power theorists, states ally to balance against threats rather than against power alone; (2) ideology is less powerful than balancing as a motive for alignment, and states sharing these ideologies are more likely to compete than to form durable alliances; (3) neither foreign aid nor political penetration is by itself a powerful cause of alignment, and neither is an effective way to gain leverage except under very unusual circumstances.  Conclusion? The burden of preserving US security is relatively light.

The alliance literature relies on balance-of-power concepts, but doubts remain regarding the universal applicability of this hypothesis.  Prior empirical and theoretical work all have problems.  Walt looks at the diplomatic history of the Middle East between 1959 and 1979, identifying 36 separate alliance commitments involving 86 national decisions.  He proposes various general explanations for international alliances, and tries to determine which of the explanations’ hypotheses are best borne out by the data.

Chapter 2
Walt generates predictions about three major factors effecting alliance behavior: (1) propensity to balance versus bandwagon, and the related effects of threats; (2) the role of ideology; and (3) the significance of foreign aid and/or political penetration.

Bandwagoning/Balancing and Threats
Balancing is “allying with others against the prevailing threat.” Bandwagoning is “alignment with the source of danger.” If balancing is more common, states are more secure, because aggressors will face combined opposition.  Balancing is at the heart of traditional balance of power theory.  The argument is that states balance because they place their survival at risk if they fail to curb a potential hegemon before it becomes too strong, and because joining the weaker side increases the new member’s influence within the alliance, because the weaker side has greater need for assistance.  The bandwagoning argument is that “states are attracted to strength; the more powerful the state and the more clearly this power is demonstrated, the more likely others are to ally with it.” Bandwagoning is a form of appeasement, as well as a way to share the spoils of victory.  

Walt argues that states tend to ally with or against the foreign power that poses the greatest threat.  States may balance by allying with other strong states if the weaker power is more dangerous for other reasons.  Because balancing and bandwagoning are more accurately viewed as a response to threats,, it is important to consider factors affecting threat level like: aggregate power, geographic proximity, offensive power, and aggressive intentions.  Perhaps most importantly, states viewed as aggressive are likely to provoke others to balance against them.  This is key: “When a state is believed to be unalterably aggressive, other states are unlikely to bandwagon.  If an aggressor’s intentions cannot be changed by an alliance with it, a vulnerable state, even if allied, is likely to become a victim.  Conclusions? In a balancing world, policies that convey restraint and benevolence are best, and appearing aggressive is costly.  A bandwagoning world is one in which states will use force because they are unafraid of alliances against them, and because they can attract allies through belligerence or brinkmanship.  

Bandwagoning is dangerous because it makes rivals more powerful and requires trust.  Hypotheses: (1) Stronger states are more likely to balance, and weak states will balance against weak states but may bandwagon against great powers; (2) the greater the probability of allied support, the greater the tendency to balance, but when allied support is certain, the tendency for free-riding or buck-passing increases.; (3) the more unalterably aggressive a state is perceived to be, the greater the tendency for others to balance against it; (4) In wartime, the closer one side is to victory, the greater the tendency for others to bandwagon against it.

Ideology and Alliance Formation
The hypothesis of ideological solidarity states that the more similar states are, the more likely they are to ally.  This hypothesis stands in sharp contrast to the hypotheses just considered, which view alliances as expedient responses to external threats.  But certain types of ideology cause conflict and dissension rather than solidarity and alignment.  In particular, when the ideology calls for the members to form a centralized movement obeying a single authoritative leadership, the likelihood of conflict among the members is increased.  Hypotheses: (1) The more similar the domestic ideology of two or more states, the more likely they are to ally; (2) the more centralized and hierarchical the movement prescribed by the ideology, the more conflictive and fragile any resulting alliance will be (Leninist movements will find stable alliances more difficult than will monarchies or democracies.); (2) the more secure a state perceives itself to be, the greater the impact of ideology alliance choices.  Therefore, ideological alignments are more likely in a bipolar world.  And therefore, the greater the advantage to the defense in warfare, the greater the impact of ideology on alliance choices.  (4) States lacking domestic legitimacy will be more likely to seek ideological alliances to increase internal and external support.  (5) The impact of ideology on the choice of alliance partners will be exaggerated; statesmen will overestimate the degree of ideological agreement among both their allies and their adversaries.

Hypotheses on Foreign Aid and Alliance Formation: (1) The more aid provided by one state to another, the greater the likelihood that the two will form an alliance.  The more aid, the greater the control by the donor over the recipient; (2) Foreign aid is a special form o balancing behavior.  Therefore, the greater the external threat facing the recipient, the greater the effect of aid on the alignment; (3) the greater the donor’s monopoly on the commodity provided, the greater tits leverage over the recipient; (4) The greater the asymmetry of dependence favoring the donor, the greater its leverage over the recipient; (5) The greater the asymmetry of motivation favoring the donor, the greater its leverage over the recipient.  Because the recipient’s security is usually more precarious, however, asymmetry of motivation will usually favor the recipient.  (6) The weaker the domestic political decision-making apparatus of the donor, the less leverage it can exert on the recipient.  

Hypotheses on Transnational Penetration and Alliance Formation: (1) The greater one state’s access  to the political system of another, the greater the tendency for the two to ally; (2) Penetration is more effective against open societies; (3) Penetration is more effective when the objectives are limited.  Therefore, the more intrusive the act of penetration, the greater the probability that it will have a negative effect on alignment; (4) Penetration is most effective when other causes contribute to the alliance.

If balancing is the norm, if ideology exerts little effect or is often divisive, and if foreign aid and penetration are rather weak causes, then hegemony over the international system will be extremely difficult to achieve.  But if the bandwagoning hypothesis is more accurate, if ideology is a powerful for alignment, and if foreign aid and penetration can readily bring reliable control over others, then hegemony will be much easier (although it will be rather fragile.)  Even great powers will view their security as precarious.
Chapter 5
The historical record in the Middle East reveals the following 4 things about the origins of alliances: (1)  external threats are the most frequent cause of international alliances; (2) balancing is far more common than bandwagoning; (3) states do not balance solely against power; as predicted, they balance against threats (geographic proximity matters); (4) offensive capabilities and intentions increase the likelihood of others joining forces in opposition, although the precise impact of these factors is difficult to measure.  

The efforts of each superpower to counter the other may take two forms, both of which are consistent with the predictions of the balancing hypothesis.  One form is to counter the other superpower by opposing its regional clients, either directly or by supporting other regional states.  Superpower support for their clients during the various Arab-Israeli wars illustrates this type of behavior.  The second form is to try to entice the opponent’s clients into realigning as the US sought to do with Egypt and Syria.  Regional states are more sensitive to threats from other regional powers, and regional powers have been relatively unconcerned about the global balance of power.  This is not to say that regional powers do not perceive the threats from a superpower.  Their perception of this type of threat usually occurs, however, when the United States or the Soviet Union is acting in support of a particular regional power.  Regional powers are unlikely to seek allies out of the fear that one superpower is becoming too powerful.  The situation is precisely the opposite, however, in relations among the regional powers themselves: regional powers seek allies against one another both because their neighbors are more dangerous and because their responses can make a difference.   Increases in offensive power encourage states to balance more vigorously.  Intentions are incredibly important because the other components of threat are not.  The principal criterion on which to base the choice of one superpower over the other will be how a given regional power perceives superpower intentions.  The obvious preference is to ally with the superpower that seems least aggressive.

Nevertheless, under certain conditions, the generally low tendency for states to join forces with the dominant power may increase somewhat.  Weak states are more likely to bandwagon than strong states, an absence of potential allies made bandwagoning more likely, and incentives for bandwagononing increased if the most threatening power was believed to be appeasable.  Because bandwagoning is more often the response of weak states, it is most unlikely to alter the global balance of power in any significant way.  

These results mean that marginal changes in the balance of power between superpowers are unlikely to make much difference and that only an enormous shift in this balance will lead regional powers to alter their international commitments significantly. Indeed, even if either superpower were to forge ahead dramatically, the ultimate effects would probably be less significant than one might suppose.  Given the overwhelming tendency for states to balance, a state whose power and ambitions are growing can expect to face ever-increasing resistance should it attempt to exploit its superior position.  Because regional rivalries are usually more important efforts to exclude the other superpower by enlisting all the regional powers under one banner are virtually certain to fail.  Because power can be used either to threaten or to support other states, how states perceive the ways that others will use their power becomes paramount.  In particular, a state’s willingness to bandwagon is heavily influenced by whether or not it believes that the threatening power can be appeased by an alliance with it.  

Balancing against a powerful state will be viewed as the more prudent response if one’s assumptions about intentions are incorrect.  Joining a defensive alliance to oppose a potential threat will protect you if the state in question is in fact aggressive. Such an alliance will be superfluous but probably not dangerous if the state in question turns out to be benign.  By contrast, bandwagoning may fail catastrophically of one chooses to ally with a powerful state and subsequently discovers that its intentions are in fact hostile.  Balancing will thus be viewed as the safer response when intentions cannot be reliably determined.    Determining intentions is not easy.  Accordingly, statesmen often seek shortcuts to identify friends and foes.  One approach is to focus on the domestic characteristics of potential partners in order to ally with those whose beliefs or principles resemble one's own.  


Randall L. Schweller, “Bandwagoning for Profit: Bringing the Revisionist State Back In,” International Security 19 (1994), pp. 72-107.

The article continues the “balancing versus bandwagoning” debate in international relations (i.e. a debate that concerns the decisions of states to create alliances with other states). The basic question posed in this debate is: do states ally more often with the weaker (i.e. do they balance?) or with the stronger (i.e. do they bandwagon?) side in a conflict? Schweller critiques the “balance-of-threats” theory that was proposed by Stephen Walt. According to this theory, in making their alliance decisions, states predominantly tend to balance (and not to bandwagon). Walt builds upon, and proposes a refinement of, the “balance-of-power” theories that focus on capabilities rather than threats as alliance determinants. Schweller, by contrast, bases his explanation on the “balance-of-interests” of states.     

Schweller’s main argument is that the theoretical literature on alliances overlooked two key factors and consequently reached the invalid conclusion that “balancing predominates.” Accordingly, bandwagoning is far more widespread than is typically assumed. The two overlooked factors are:
(1)    The profit-oriented aspect of bandwagoning – bandwagoning is not simply the opposite of balancing and cannot necessarily be perceived as giving in to threats with the aim of achieving greater security. Instead, it can be driven by the opportunity for gain and profits.  
(2)    Bandwagoning is a preferred alliance pattern for revisionist states (i.e. for the states that are more likely to pose threats) – the debate to date was conducted under the premise that “alliance choices are best examined as a response to threat.” And indeed, for balancing to take place it is necessary that a significant external threat will be present. In that sense, Walt offers a theory that explains how states respond (the dependent variable) to external threats (the causal variable). Bandwagoning, however, does not necessarily require the presence of an external threat. This is particularly true in the case of revisionist states that aspire to alter the status quo. Since Walt’s case selection was biased towards cases that were characterized by the presence of a significant external threat, he falsely concluded that balancing is the predominant form of alliance. Similarly, Schweller claims that Walt’s definition of bandwagoning is very close to the concept of capitulation and does not fully capture the concept’s meaning.    

According to Schweller’s “balance-of-interests” theory “the most important determinant of alignment decisions is the compatibility of political goals, not imbalances of power or threat.” Therefore, the important distinction that should be made is between status-quo and revisionist states. A status-quo state will join the status-quo coalition whereas “dissatisfied powers, motivated by profit more than security, will bandwagon with an ascending revisionist state.”

After establishing that security considerations are not the only motivations for allying and that the prospect of political gains is more likely to lead to alliances of the bandwagoning type, Schweller lists a series of bandwagoning scenarios. These include: (1) Jackal bandwagoning – an opportunistic revisionist power joins a powerful revisionist state (the bandwagon) with the hope for profit. (2) Piling on – similar to jackal bandwagoning but it occurs when the war has already been determined. (3) Wave of the future – states bandwagon with the stronger side because they believe that it is the wave of the future (e.g., communism in the 1950s or liberal democracy in the 1990s). (4) Domino effect – a metaphor of infection or falling dominoes that is commonly used by practitioners to justify their bandwagoning policies. To demonstrate this effect, Schweller cites the series of peace negotiations that were launched in the Middle East (in 1993-4) following the Israeli-Palestinian DOP of 1993 (…).                      

Schweller’s balance-of-interests theory of alliances is based on two levels. At the unit level, it is assumed that different states have different preferences. He identifies four types of states along the axis that ranges from satisfied (status-quo) to dissatisfied (revisionist) states. The state type are: Lions (self-preservation status quo states), Lambs (self-abnegation status quo states), Jackals (limited aims and self-extension revisionist states), and Wolves (unlimited aims and self-extension revisionist states). Jackal states are the most likely to bandwagon when they identify an opportunity for profit. Lamb states are more likely to appease or indulge in wave-of-the-future bandwagoning due to their weakness and lack of non-security related ambitions. Wolf states are “hungry” and most likely will constitute the bandwagon itself. At the systemic level, “the stability of the system depends on the balance of revisionist and conservative forces. When status-quo states are far more powerful than revisionist states, the system will be stable.” And vice versa, when a strong revisionist coalition will be present a change in the system is very likely to take place.

The important distinction is, then, between status quo states, which seek self-preservation and are security maximizers, and revisionist states, which are more willing to bear the costs of war for the purpose of non-security expansion.


John J. Mearsheimer, The Tragedy of Great Power Politics. New York: Norton, 2001. Ch. 5 and Ch. 8

Chapter 5: Strategies for Survival
    Based upon the assumptions of the preceding chapters (state seeks hegemony, primacy of military power with focus on army), the author argues that states seek four main objectives: 1) regional hegemony 2) relative wealth maximization 3) preeminent land power 4) nuclear superiority. Then he categorizes two different types of strategy: strategies to gain power (war, blackmail, bait and bleed, bloodletting) and strategies to check aggressors (balancing and buck-passing).
    Four objectives: Since global hegemony is not feasible from the stopping power of water, great powers seek regional hegemony while strive to prevent rivals in other areas from gaining hegemony, because they can still threat each other by helping to upset the balance of power in each other’s backyard. Great powers also want to maximize their share of world’s wealth (relative wealth), ultimately to gain a military advantage over rivals. This leads the great powers to prevent rivals from dominate the wealth-generating areas of the world (During the Cold War, the U.S. focused attention on Europe, Northeast Asia, and the Persian Gulf). Great powers seek to dominate the balance of land power. Lastly, great powers seek nuclear superiority over their rivals (in case it succeeds, it will make a global hegemon and the balance of land power would be insignificant).
    Strategies to gain power: War is the most controversial strategy, and there are many voices that war is a losing option (i.e., aggressors lose, nuclear weapons make war impossible, too high cost) the author asserts conquest can still improve a state’s power position by gaining access to material basis and shift the balance of power in the victor’s favor. Blackmailing (threat to use military force against the opponent) can produce a similar outcome (especially works well against minor powers that have no great-power ally) even between the great powers. Bait and bleed involves causing two rivals to engage in a protracted war, but it is difficult to trick rival states into starting a war. Bloodletting is a variant of bait and bleed strategy; it is to any war between one’s rivals turn into a long and costly conflict that saps their strength (not causing the war itself).
    Strategies for checking aggressors: balancing means to maintain current balance of power by accepting direct responsibility of defense either jointly or independently; its initial goal is to deter the aggressor, but if that fails, the balancing state will fight the ensuing war. To make balancing work, a state can 1) send signals that shows its commitment to current balance of power 2) create a defensive alliance (external balancing) 3) military buildup (internal balancing). Buck-passing is an attempt by a state to get another state to bear the burden of deterring or possibly fighting an aggressor, while itself remains on the sidelines. Four measures to facilitate buck-passing: 1) seek good diplomatic relations with the aggressor (to make the aggressor focus on other possible ‘buck-catcher’) 2) maintain cool relations with the intended buck-catcher 3) mobilize additional resources of their own to make buck-passing work (make itself strong so that the aggressor would turn to an easier target – the buck-catcher) 4) Allow or facilitate the growth in power of the intended buck-catcher.
A state has a strong tendency for buck-pass or free-ride inside balancing coalitions despite the danger of wrecking the coalition. Additional benefit will arise when the aggressor and the buck-catcher goes into a war of attrition. It is an economical way to deal with threat(s). But buck-catcher may 1) fail to deter 2) turn into a new aggressor. On the other hand, great powers that care about their survival ‘should not’ appease or bandwagon, while those can be strategy for the weak. Mearsheimer criticizes Kenneth Waltz’s idea that security competition drives great powers to imitate the successful practices of opponents, thus consolidating the status quo. Mearsheimer’s main points are that states not only emulate successful balancing but also successful aggression, and that innovation, not only imitation, is also prized.

Chapter 8: Balancing versus Buck-Passing
    In this chapter, Mearsheimer elaborates relationship between the two strategies to defend the balance of power – balancing and buck-passing. He suggests that the choice between balancing and buck-passing depends on the distribution of power among the major states, and geography. Assuming three major archetypes of power distribution (Bipolarity: two powers with equal mights. Unbalanced multipolarity: more than three powers with one potential hegemon included. Balanced multipolarity: more than three powers with no aspiring hegemon), he argues that buck-passing cannot exist in bipolarity because there is no third party – therefore, multipolarity is a condition for buck-passing to take place. It is less likely to happen in an ‘unbalanced’ multipolar system, because the threatened states have a strong incentive to work together to prevent the potential hegemon from dominating their region. Geography is another criterion; if the threatened state shares a border with the aggressor, it is likely to balance. If there exists a barrier (i.e., territory of another state or a large of water) then a state is likely to buck-pass.
    Mearsheimer suggests five historical examples to support his argument: 1) Revolutionary and Napoleonic France (1789-1815) 2) Bismarckian Prussia (1862-70) 3) Wilhelmine Germany (1890-1914) 4) Nazi Germany (1933-41) and 5) The Cold War (1945-90). In cases of Wilhelmine and Nazi German expansions, the U.S. reaction was to pass the buck to other European great powers. But as the Cold War case amply shows, the (potential) aggressor (Soviet Union) was the most powerful both in Europe and Northeast Asia and the U.S. was the only nation capable of containing it. Buck-passing was not a viable option, although the U.S. still had intention to buck-pass. The case of Bismarckian Prussia supports a claim that the buck-passing behavior can exist under multipolarity with potential hegemon (i.e., the U.K and Russia supporting a unified Germany hoping that it will become a future buck-catcher against each other). Geography also worked to discourage buck-passing against Wilhelmine Germany but to encourage it against Nazi Germany and Napoleonic France: Wilhelmine Germany shared a lengthy border with France and Russia, but there were many East European countries functioned as buffer between Nazi Germany and Russia, which made Russia less interested in containing Nazi Germany.


Robert Powell, In the Shadow of Power. Princeton: Princeton University Press 1999. Chapter 5.

The main results
Powell builds a model of alignment decisions by states after one of the states in the system attacks.  His conclusions are as follows (Figure 5.14, p. 195): if the returns to scale in the aggregation of military capabilities are small, a state prefers to remain neutral.  If the returns to scale are moderate, a state either remains neutral or bandwagons.  The smaller the returns to scale, the more likely it is to wait; the higher the attacker’s willingness to fight, the more likely it is to bandwagon.  Finally, if the returns to scale are high, a state will not remain neutral.  It will bandwagon when the attacker’s willingness to fight is equal to that of other states, and it will balance when the attacker’s willingness to fight is higher than that of other states.  

The model

Powell’s model is briefly summarized below (Game tree: Figure 5.1, p. 158).  There are three states.  The initial distribution of power is defined in terms of probabilities of a state defeating another state when fighting in isolation, and these probabilities are defined for each pair (3 pairs total).  The distribution of benefits is defined by a share of territory belonging to each state.  In the first stage, a potential attacker can choose either not to attack, at which point the game ends, or to attack one or both states.  If it attacks one state, the other has the following options: wait, balance (join the attacked state), or bandwagon (join the attacker).  The game ends any time a single state defeats a coalition (the winner gets all territory).  If a coalition is victorious, the winners bargain with one another over the distribution of benefits.  A state’s payoffs are increasing in its share of territory and decreasing in its cost of fighting.  A state’s cost of fighting, in turn, is decreasing in a state’s willingness to fight, is increasing in the size of its adversar(y/ies), and is increasing in its relative power vis-à-vis its ally (the more powerful ally bears the larger share of the fighting).  Finally, the relative power (a function of military capabilities) of a coalition depends on how capabilities cumulate.  If the returns to scale are decreasing /constant /increasing, a coalition’s joint capability is smaller than /equal to /greater than the sum of its parts.

Alignment Decisions
 If the attacker’s power is relatively low and if the returns to scale in the aggregation of military capabilities are low, a state that was not attacked will prefer to remain neutral.  By doing so it avoids paying the cost of fighting and plays a bargaining game with the victor.  If the above two conditions hold, the victor will be satisfied (it’s relative power will not be disproportionately greater than its territorial possessions), and the neutral state will not have to make concessions.            
            On the other hand, if the above conditions are reversed, the victor will emerge from the fight with its power disproportionately large compared to the additional territory it acquired.  This makes neutrality costly, since concessions will have to be made by the neutral state to appease the victor.  Thus, a state will join the fight.
            The tradeoff between balancing and bandwagoning is as follows.  “Balancing entails a lower probability of being part of the winning coalition but being relatively more powerful if the coalition prevails.  Bandwagoning entails a higher probability of being part of the winning coalition but being relatively weaker if the coalition prevails” (178).  The latter usually outweighs the former.  This is because while the payoff to balancing is monotonically decreasing in the attacker’s power, the payoff to bandwagoning is increasing in it up to a certain point (Figure 5.8, p. 179).  Up to that point, the increase in the attacker’s power improves the coalition’s probability of winning and is still not large enough to make the attacker dissatisfied and in need of appeasement after the victory.  
            However, if the attacker is more willing to use force than the other two states, balancing becomes a more attractive option when the returns to scale are high.  When a state bandwagons with the attacker, and the coalition prevails, the state will have to make larger concessions during the bargaining stage to appease the attacker who is willing to use force.  Meanwhile, payoff to balancing is invariant to the attacker’s resolve (Figure 5.12, p.191).  

The decision to attack.
“The potential attacker does not attack if the distribution of power roughly reflects the distribution of benefits, and the returns to scale are not too large.  If, by contrast, there is a moderate disparity between the distributions of power and benefits, the potential attacker attacks the weaker of the other two states in the correct expectation that the stronger state will find fighting too costly and will wait… If the attacker is still more powerful…, both [states] will bandwagon.  Anticipating this reaction, [the attacker] now attacks the larger of the two states, after which the smaller state aligns with [the attacker]” (184).   


Dan Reiter, “Learning, Realism, and Alliances: The Weight of the Shadow of the Past,” World Politics 46 (1994), pp. 490-526.

What are the causes of states’ preferences for alliance or neutrality? An alliance is defined as a formal commitment to contribute military assistance in the event one of the alliance partners is attacked. When deciding whether to enter an alliance or remain neutral a nation must consider the benefits of alliance (extended deterrence in peacetime, military assistance in war) against the risk of being involved in wars with no direct interest to he nation. Neutrality decreases the risk of involvement in the wars of other nations at the cost of no allies to deter potential aggressors or defend against attacks. Whether a state chooses alliance or neutrality is likely to depend on whether is believes that alliance poses too great a risk of involvement or if it believes that international cooperation is necessary to protect its security.

The author suggests that the decision is often made on the base of learning – an application of information derived from past experiences to acquire understanding of a particular policy question (in this case – whether to join an alliance). Learners tend to keep analogies simple. The danger is that relying on overly simple lessons and neglecting important historical details can lead to misguided choices. The model thus assumes that nations can draw one of two lessons from a formative event: either that neutrality best protects national security or that alliance best protects national security. The analysis is limited to alliance choices of minor powers, which have more simple interests.

Experiences in wars are formative of beliefs about alliances. Since alliance policy is the centerpiece of a minor power’s wartime foreign policy, it will be assigned responsibility for success or failure in the war, perhaps even if the minor’s alliance choice was irrelevant to its fate. Systemic wars in which great powers fight each other are the most earth-shaking events and therefore are the most likely of wars to be formative. Further, in systemic wars more than in other wars minor powers are more likely to attribute their fortunes to their alliance because of their relative weakness. The general proposition is thus: systemic wars are formative events that determine minor powers’ beliefs concerning whether neutrality or alliance with a great power is preferable.

In a systemic war a minor power attempts to be wither allied or neutral. Whether the outcome was failure or success dominates the drawing of lessons, where failure encourages innovation and success promotes continuance. The definitions of failure and success:
-    If a minor power attempted neutrality in a systemic war and was not invaded, the experience is considered a success; otherwise – failure.
-    If a minor power attempted being allied, was on the winning side and was not invaded – success. If it was allied and invaded but acquired more population in postwar territorial settlement than it lost in the war – success. If a state was allied and on the losing side; or was on the winning side, was invaded but did not recover as much population in postwar settlement as it lost during the war – failure.

The author suggests two different learning hypotheses:
1.    A state’s individual experiences dominate its belief formation, so that its national experience in war determines what lessons are drawn. According to this logic, a minor power can attempt either alliance or neutrality with a great power in a systemic war. If it experiences failure, it will switch policies following the war; if it experiences success, it will continue that policy.
2.    States garner the same lesson from a systemic event, regardless of individual experience. A minor power weighs the formative event experiences of all minor powers in order to determine a composite lesson about the relative merits of alliance and neutrality. All minor powers will adopt policies in congruence with the system wide lesson in the years following the war.

 Reiter also derives several hypotheses from Walt’s balance of threat theory:
1.    If a systemic war appears to be impending, a minor power is more likely to prefer alliance with a great power, either by joining the revisionist power or by joining the defending powers in an attempt to balance against the revisionist threat.
2.    If a minor power perceives that a systemic war is imminent, the greater the military disadvantage it faces concerning the potential revisionist great power, the more likely it will be to prefer great power alliance.
3.    If a minor power perceives that a systemic war is imminent, it is more likely to prefer a great power alliance if it is geographically exposed to the potential revisionist than if it is not.
4.    A minor power will prefer one-way defense commitments that will not entangle it in war. It is less likely to prefer great power alliance if one or more great powers have made non-alliance defense commitments to it than if no such commitments have been made.   
5.    A minor power can also be threatened directly on a more specific issue. The level of perceived direct threat is positively correlated with the probability that a minor power will prefer alliance with a great power.

Reiter tests the competing theories, learning/balance of threat, using a dataset in which cases are observations of peacetime behavior of minor powers, specifically whether or not the minor power preferred alliance with a great power or not at a given time. The formative events are the two world wars. For each minor power included, there are several observations following each of the world wars to allow for variation in alliance policies across time as well as variation in the level of threat. In the post WWI period behavior was coded in 1921,1927,1933,1939; in WWII period – 1949,1955,1961,1967. The empirical tests show that individual experiences are powerful determinants of alliance preferences, and that variations in external threat, in contrast to the predictions of balance of threat, have very little effect. Further, the marginal effect observed is opposite to that predicted by balance of threat theory, suggesting that minor powers tend to follow buck-passing/neutrality logic more frequently than balance/bandwagon logic. An important caveat is that the paper presents only a limited test of balance of threat theory (it includes only minor-great power alliances and relatively high threats).
Individual learning explains the peculiar checkerboard patterns of neutrality and alliance since World War I. Switzerland, the Netherlands and Belgium attempted neutrality in WWI. Neutral Belgium was invaded in 1914, an experience that played a key role in causing it to revamp its foreign policy toward alliance following the war. Switzerland and the Netherlands emerged unscathed, reinforcing their neutral orientations. All three again attempted neutrality in WWII, and the two that were invaded, Belgium and the Netherlands, joined NATO after the war, whereas Switzerland remained neutral.  


Smith, Alastair. 1995. "Alliance Formation and War." International Studies Quarterly, 39 (4): 405-426.

A game-theoretic model in which three states interact. At node 1, state A may either not attack or attack. If state A does not attack, the outcome is the status quo (SQ). If state A attacks, state B may retaliate or surrender at node 2. If state B surrenders, the outcome is acquiesce (ACQ). If state B retaliates, then state C can either stay neutral or join one of the sides. B's preferred outcome is the status quo. A's preferred outcome is acquiesce. In the interesting games, there is a cost, f, to forming an alliance. There is a cost, h, to withdrawing from an alliance (C is in an alliance with B, but when war starts, C does not honor its commitment, which is the case empirically among 75% of war participants according to (Kim 1991)). There is a cost, w_i, of violence in war to state_i. Alliances are often unreliable, leading to expected payoffs.  Alliances only occur between states that have similar preferences, i.e., if state C prefers ACQ to SQ, it allies with state A, and vice versa.  Because both alliance creation and alliance failure is assumed costly to both allied partners, alliances are not created with perfect information when the alliance will be reliable and have an effect on the actions of A or B (either A decides not to war if there is a defensive alliance (B-C) or B decides not to retaliate if there is an offensive alliance (A-C).  Previous empirical work that attempts to find a relationship between alliance and war in the aggregate asks the wrong question. The right question distinguishes between defensive and offensive alliances and their particular effects: defensive alliances both discourage war and encourage retaliation. The aggregate effect is ambiguous. Offensive alliances have a similar ambiguous effect. Unreliable alliances (where C is likely to shirk if called upon to join B) if joined with a high cost from a broken alliance, encourages A to attack (because of the high cost of alliance failure to B, leading B to acquiesce). The empirical evidence that nations intervene on behalf of their allies in only 25% of wars is explained by the theory that unreliable alliances are selected into the sample (state A chooses to fight state B only if it thinks its alliance with state C is unreliable).


Erik Voeten, "Outside Options and the Logic of Security Council Action," American Political Science Review 95:4 (December 2001), pp. 845-858.  

Using a game-theoretic framework, it is shown that an outside option (the ability to act outside of the international organization) possessed by a superpower in an international organization composed of veto players, gives that superpower the ability to gain favorable agreements with other veto players. The game is modeled after the UN. Security Council with three veto players: the US as "superpower", a US "ally", and a "Challenger".

The outcome space is a Euclidean unidimensional line, with the superpower's ideal point being 0 and the Challenger's ideal point being 1.  The Ally is somewhere in between. The base utility of each player is the negative space between the outcome and the player's ideal point. The status quo is between 0 and 1. The superpower can force the outcome to its ideal point (0) but to do so without the agreement of one or both veto players leaves the superpower with one or both of costs C_a and C_c.  Unilateral action is the worst case scenario for both the Challenger, and depending on the location of the status quo, sometimes for the Ally as well. Unilateral action is credible, however, whenever the costs of unilateral action are less for the Superpower than the status quo.

Bilateral action has two conditions: 1) the superpower must prefer the utility costs of the compromise outcome with the Ally, as well as the costs of excluding the challenger, to the payoff from unilateral action (even if the condition of unilateral action is not satisfied); this condition ensures that the Ally cooperates, and 2) that at least one of two additional conditions obtains: a) the agreement between the Ally and Superpower is better than the status quo for the Ally, or b) the outside option of the Superpower is credible (unilateral action is credible, as explained above).

Multilateral action will occur that improves the position of the superpower and degrades the position of the Challenger if either outside option (unilateral or bilateral) is credible.

If non-permanent members are added to the model (Voeten adds two with vote but not veto power), they can only affect the outcome if they are closer to the superpower's ideal point than to the Ally's ideal point. In this case they improve the outcome for the superpower. Additional permutations of the model are offered with incomplete information and partial commitments.

Voeten gives multiple examples, one being President Bush threatening to unilaterally pull out of the Anti-Ballistic Missile treaty as a way to encourage Russia, China, and Europe to agree to a new multilateral treaty structure.


Sophie Meunier, "What Single Voice? European Institutions and EU-US Trade Negotiations," International Organization 54:1 (2000), pp. 103-135.

The article asks how the different institutional negotiation rules affect the bargaining capabilities of the EU in international negotiations. The more general question is “what is the impact of internal EU institutions on international outcomes?” To address this research topic, the author develops “an institutional model of the bargaining power of the EU in international trade negotiations.” Bargaining power is defined as the ability of a negotiating actor to get the best possible deal in the negotiation.

The model draws on the two-level game literature (e.g., Putnam, 1988) and is based on three variables: (1) Internal voting rules in the EU – with two possible values of unanimity or majority voting; (2) The nature of the delegation to the negotiating agent – with two possible values of restricted or extended delegation; (3) The negotiating context relative to the status quo – with two possible cases, a reformist and a conservative case. In the conservative case, the preferences of the EU member states, in relation to those of the opponent (i.e. the US), are closer to the status quo. In the reformist case, the preferences of the EU member states, in relation to those of the opponent, are further away from the status quo. That means that in reformist cases, the EU will challenge the US to modify existing arrangements. For example, it might request the US to lower its tariffs. In the conservative case, by contrast, the US would challenge the status quo and the EU will attempt to preserve it. Thus, voting rules and negotiating competence (i.e. the extent of delegation) are the model’s independent variables. By using the model, we can better predict, for a given negotiating context (i.e. reformist or conservative), “both the probability that the negotiating parties conclude an international agreement and the substantive outcome of the negotiations.”

More specifically, the author suggests that in conservative cases (i.e. in trade negotiations that are meant to challenge the EU’s status quo), unanimity voting and restricted delegation make the EU a tougher bargaining partner. The opposite is also true, majority voting and extended delegation, in similar conservative cases, will lead to less EU bargaining power. One explanation to that is that when unanimous approval is required, the common position that is eventually reached is the lowest common denominator. This is so since the default position, according to EU rules, is to maintain the status quo. By contrast, in reformist cases (i.e. when the EU seeks to change the status quo), Meunier suggests that the institutional design has a smaller role in determining the final outcome of the negotiation. However, it expects it to have an impact on the likelihood of the negotiation. The reason for that is that in the reformist case, the opponent will ultimately determine how much he will agree to deviate from the status quo regardless of the EU’s institutional arrangements. In other words, the EU’s bargaining power in such cases is weak. 

Member states, however, do not benefit equally from being forced to negotiate their external trading arrangement in a unified front with their fellow EU states. For instance, small states with conservative preferences can amplify their bargaining power by vetoing any deal that does not fit their agenda. By contrast, states with median preferences can benefit more from a majority vote system that will settle on terms that better reflect their interests.