In international politics ideas do matter as they can condition the exercise of ‘power’. Since the concept of power has been addressed mainly by realist theorists as the core of the international anarchic system, power politics is strongly associated with realist theory. However, constructivists view realism as a rationalist theory focusing on materialism, one that has marginalized the role of ideas in power politics by emphasizing the deterministic role of international anarchy and treating state identity and interests as givens. In this context, Alexander Wendt,1) a constructivist, describes the creation of ideas,2) that is, the formation of intersubjective understandings and knowledge in a given social and historical context, as something that can facilitate either conflict or cooperation as a type of feedback loop leading to either vicious or virtuous cycles while denying anarchy’s deterministic role and pre-given characteristics of state identities and interests.

In particular, structural realism, which emphasizes parsimony over theoretical depth, fits constructivist criticism due to its failure to address the impact of ideas on power politics. Nevertheless, I argue that the constructivist critique (that realism ignores ideational factors by virtue of being rationalist theory) is not entirely true, because various realist theories have divergent assumptions and conceptualizations, allowing realists to escape from the strictures of rationalist theories. All realist theories cannot be placed in a single rationalist paradigm; instead, they must be placed in different paradigms, although they are all branded as realism. In particular, some classical realist and various modified realist theories (especially neoclassical realism) implicitly deal with the impact of ideas on power politics and state behaviors, allowing enough potential for the integration of ideas into the realist canon. From this perspective, the contribution made by constructivists can even be seen as being supportive, rather than in fundamental rivalry with or in contradiction to realist theory.

In the sections that follow, I review the role played by ideas and the intersubjective structures that ideas generate, contributing to the creation of different qualities of the international system in the constructivist tradition; critically review particular works germane to structural realism’s alleged dismissal of ideas; attempt to defend realist theory from constructivist challenges by showing how the role of ideas is addressed implicitly in some classical realist and various modified realist theories, demonstrating how ideas implicit in the classical and modified realist repertoire can contribute to enhancing our understanding of international politics; and finally conclude with comments on the direction of development for improving realist theories, especially those related to the recent notable phenomena (international terrorism) in world politics.

1)Alexander Wendt, “Anarchy Is What States Make of It: The Social Construction of Power Politics,” International Organization 46-2 (1992), pp. 403-407.  2)Legro defines the term “idea” as the “collective beliefs of societies and organizations about how to act.” This definition is also strongly associated with “intersubjective understandings” and “knowledge” of a particular group in a given social and historical context. Jeffrey W. Legro, “What China Will Want: The Future Intentions of a Rising Power,” Perspectives on Politics 5-3 (2007), p. 522.

By treating realism as a faulty rationalist theory that focuses only on materialism and rationalism, Wendt3) claims that constructivism highlighting idealism is logically incompatible with such realism.4) With respect to this incompatibility, John G. Ruggie5) argues that a key distinction between the rationalist and constructivist understandings of ideas is that rationalists maintain that ideas are subjective, while constructivists assert a place for “intersubjective beliefs” constituting “social facts.” If beliefs are subjective, then their meanings are not shared across actors; they cannot coordinate action. In contrast, if beliefs are intersubjective, then they may coordinate action, as their meanings are internalized and maintain constancy across actors.

In the constructivist understanding, ideas are intersubjective knowledge, which forms a “collective intentionality” constituting the rules of the game in the system. The foremost example of this is the state system and its sovereignty.6) Since the rules of the game are not held to be fixed and exogenous, even the most basic unit in the international system, the state, is subject to change. Based on this viewpoint, constructivists see the nature of the state system as being liable to change depending on the changes in the intersubjective understandings that offer the cognitive framework by which institutions exist. In this respect, all possible systems of international relations are derived from various intersubjective understandings, with self-help system being but one of the possible systems that may arise.

Furthermore, Wendt holds that anarchy is not deterministic, being instead “what states make of it,”7) so that anarchy is a permissive condition, in which predator states, rather than human nature as asserted by classical realists, generate the certain harmful intersubjective understanding by which they themselves are constituted. Thus, constructivists see the role of a limited number of predator states as creating the possible system that compels selfhelp. Wendt holds that self-help is “an institution, one of various structures of identity and interests that may exist under anarchy,” by rejecting the notion of structural realism that self-help is exogenously imposed to the process of interaction among states.8) In this context, security dilemma is also a social structure of intersubjective understanding in which state actors harbor so much suspicion that they assume the worst of one another’s intentions.9) Further, Wendt emphasizes the importance of process over structure as a crucial factor affecting self-help system and power politics. He argues, “selfhelp and power politics do not follow either logically or causally from anarchy, and ⋯ if today we find ourselves in a self-help world, this is due to process, not structure.”10)

Based on the above arguments focusing on the changing concept of process, not on the fixed one of structure, Wendt paves the way for understanding anarchy as “having multiple meanings for different actors based on their own communities of intersubjectivity, understandings, and practices.”11) From this perspective, characteristics of anarchic international systems can vary, based on the changes in the intersubjective understandings among state actors. In the system where the dominance of predation has come to constitute the core of intersubjective knowledge guiding state action, self-help rather than collective security is almost certain to prevail (the so-called Hobbesian culture). By contrast, in the system where there is a strong intersubjective understanding that cooperation rather than conflict is the principle mode of state action, collective security is likely when confronted with an emergent predator state; further, in this system, belligerent factions recognize that they can best achieve their interests by remaining peaceful with each other (the socalled Kantian culture). In the constructivist world, ideas play a crucial role in constituting identities and interests of state actors, contributing to the changes in characteristics of anarchic nature of the international system. Therefore, constructivism rejects the reification of the self-help system, holding instead that the changes in the intersubjective understandings, which leads to either self-help or collective security, is the result of state agency rather than the system’s structure or inherent characteristics of human nature.

Thomas Risse also argues that constitutive role played by ideas is a crucial contribution by constructivism to the study of international relations theory, noting that understanding “intersubjective knowledge” (i.e., ideas) allows us to explain both systemic stability and systemic change.12) Ideas precede the social structures involving actors, while at the same time ideas are constituted by actors; ideas are therefore made up of both structure and agency.13) Thus, unlike rationalist theories, state identities and interests are not given and the function of international anarchy is no longer self-deterministic due to the constitutive role played by ideas. In Risse’s view, since ideas occupy an ontological middle ground between individualism (e.g., state actors) and structuralism (e.g., the system’s structure), they can be defined in terms of not only internalized meaning but intersubjective culture as well, affecting the power politics and state behaviors.14)

In addition, Martha Finnemore claims that the convergence of state design and recurrent regularities in the domestic political structures is created by the diffusion of intersubjective and normative understandings among actors in a given social and historical context, rather than by the purpose of achieving functional utility.15) From this perspective, the acceptance of rationality and bureaucracy in contemporary societies can be seen as a natural outcome of the expansion of Western culture in a supportive social and historical context that must be taken as a variable in order to be understood.16) In other words, in the constructivist view suggested by Finnemore,17) rationality and bureaucracy have spread as the result of the diffusion of Western culture through the favorable social and historical process. Thus, ideas, that is, the diffusion of intersubjective and normative understandings among actors, lie behind utility, but utility does not lie behind ideas.

In terms of the constructivists’ stance, if certain ideas gain a generally accepted status among state actors in a supportive social and historical context, this collective meaning, i.e., accepted ideas, can influence state behavior, reproducing and redefining its identity. Thus, unlike the assumptions of rationalist theories, the state is no longer a predefined actor as a unit of analysis due to the constitutive role played by ideas, so that state identities and interests can change. Wendt also notes that state actors obtain “identities—relatively stable, role-specific understandings and expectations about self—by participating in such collective meaning.”18)

In the view of constructivists, state behaviors can be guided by ideas rather than by a subjective notion of utility as asserted by rationalist theories; therefore, state identities are also changeable by the changes in the intersubjective understandings, in which state actors are involved, in a given social and historical context. For example, with regards to the reason for the acceptance of international human rights norm by the Soviet Union and its allies in the Cold War era, Daniel C. Thomas notes: “States that doubt their legitimacy in international society [like the Soviet Union and its allies] will seek recognition and legitimation from other states, even if this means endangering other interests.”19) Such acceptance of human rights norms could apparently occur largely because leaders of the Soviet bloc cared about what leaders of the Western bloc thought of them. In a similar vein, Cynthia Weber also contends that unlike rationalist theories’ assertion, identities and interests of states have no pre-given nature, so that they are not fixed in international politics.20)

The above stance of constructivism emphasizing the impact of ideas on state behaviors and power politics calls the basis of structural realism directly into question. According to this perspective, the state is not a black box, as structural realists argue, but consists of different individuals and institutions trying to develop collective understanding (ideas) of the given situation through cognitive and communicative processes. However, I argue that this constructivist stance does not pose the same threat to some classical realist and various modified realist theories, especially neoclassical realism, because they can allow enough potential for integrating ideas into their realist repertoire. Before addressing these theories, I first look to the failure of structural realism in incorporating ideas into its realist paradigm.

3)Alexander Wendt, op. cit., pp. 391-425.  4)Heikki Patomaki and Colin Wight, “After Postpositivism? The Promises of Critical Realism,” International Studies Quarterly 44-2 (2000), p. 213.  5)John Gerard Ruggie, “What Makers the World Hang Together? Neo-Utilitarianism and the Social Constructivist Challenge,” International Organization 52-4 (1998), p. 869.  6)Ibid., p. 870.  7)Alexander Wendt, op. cit., pp. 407-410.  8)Ibid., p. 399.  9)Ibid., p. 394.  10)Ibid.  11)Ted Hopf, “The Promise of Constructivism in International Relations Theory,” International Security 23-1 (1998), p. 174.  12)Thomas Risse, “Let’s Argue!: Communicative Action in World Politics,” International Organization 54-1 (2000), pp. 1-39.  13)Ibid., pp. 4-6.  14)Ibid., p. 5.  15)Martha Finnemore, “Norms, Culture, and World Politics: Insights from Sociology’s Institutionalism,” International Organization 50-2 (1996), pp. 336-337.  16)Ibid., pp. 328-330.  17)Ibid., pp. 325-347.  18)Alexander Wendt, op. cit., p. 397.  19)Daniel C. Thomas, The Helsinki Effect: International Norms, Human Rights, and the Demise of Communism (Princeton, NJ: Princeton University Press, 2001), p. 267.  20)Cynthia Weber, International Relations Theory: A Critical Introduction (New York: Routledge, 2001), p. 60.

In contrast to the classical realist camp focusing on human nature as a fundamental cause of international conflict, structural realism sees the conflict as being derived from the anarchic nature of the international system. In this context, the classic statement of structural realism lies in the insistence that “self-help is necessarily the principle of action in an anarchic order.”21) Thus, states in a system of self-help are frequently unable to cooperate, even when sharing common interests, because states care about relative gains.22)

A pioneer in structural realism, Kenneth Waltz argues that the primary purpose of states is to survive in the anarchic international system.23) For this purpose, states try to maintain their relative power vis-à-vis others within the system.24) Thus, the “distribution of capabilities across units” defines the structure of the anarchic international system.25) Waltz assumes that great powers as prudent and status quo states will only pursue a moderate amount of power in order to ensure their security and to preserve the status quo balance of power in a self-help environment. Also, based on the Waltzian balance-of-power logic, the possibility of a major war is less likely because expansions by great powers or potential hegemons are always checked by balancing coalitions. Therefore, according to Waltz, balances of power in the anarchic structure are a recurrent automatic phenomenon due to the constraints of the anarchic self-help system, although the US-led unipolarity has continuously been maintained today. Thus, Waltz’s realist theory is typified as defensive realism.

In particular, in relation to the measurement of power, Waltz argues that distribution of power is composed of various material factors (e.g., resource endowment, economic capability, territory, population) and nonmaterial factors (political capacity and stability).26) However, Waltz fails to elaborate how power is actually measured. Further, Waltz does not consider the impact of ideational factors on the measurement of power. Thus, he ignores the fact that the measurement of power can be elaborated and manipulated by ideational factors like changes in intersubjective understandings between actors—how opposing states’ policymakers have actually perceived a counterpart’s power, intentions, and identities in various social and historical contexts.

For instance, the Soviet power was perceived to be a very aggressive one to the United States during the Cold War, but the current Russian power is not perceived to be as aggressive to the United States. The crucial reason for changing the US threat perception is that Russia’s identity after the Cold War is totally different from that of the Soviet Union during the Cold War, rather than the factor that Russia’s power is weaker than that of the Soviet Union. However, structural realists, including Waltz, as rationalist theorists do not consider changes in identities of state actors to be an important factor affecting the power politics, because they assume that these identities have been dominated by the predetermined system’s structure imposing impossibility of intersubjective understandings and knowledge on the state actors. Thus, these identities have been assumed to be exogenous, not endogenous, to parsimonious accounts of international politics by structural realism.

Meanwhile, according to John J. Mearsheimer’s, in order to mitigate fear in the anarchic structure of the international system, states pursue power maximization rather than security maximization.27) In his understanding, because “states can never be certain about other states’ intentions” due to the anarchic nature of international system,28) it compels great powers to behave as if they were predator states and struggle with each other for maximizing their relative power position. Mearsheimer believes that Waltz’s theoretical world suffers from a “status quo bias,” which contains only “status quo powers” seeking moderate amount of power as the best route to ensuring security.29) In Mearsheimer’s view, the international system compels states to seek as much power as they can because “survival mandates aggressive behavior” in the international system.30)

Also, unlike Waltz, Mearsheimer holds that the possibility of the formation of balancing coalition to check an emergence of potential hegemon is lower especially in a multipolar system because self-interested states prefer to pass the buck to others in order not to have the burden of security costs.31) Further, he argues that states inherently want to pursue “successful aggression” rather than “successful balancing behavior” because they believe that “aggression pays.”32) Thus, Mearsheimer’s theory is typified as offensive realism predicting a greater possibility of conflict and war, compared to Waltz’s.

However, great powers sometimes pursue nonsecurity goals (e.g., US intervention in Kosovo in 1999), which Mearsheimer admits is a limitation of his theory. He explains: “these limitations stem from the fact that nonstructural factors sometimes play an important role in determining whether or not states goes to war. States usually do not fight wars for security reasons alone.”33) Therefore, nonstructural factors, especially ideational factors, which affect state behaviors and power politics, must be added to this realist repertoire as an intervening variable in order to better explain various state behaviors.

Although there is a dispute among the advocates of structural realism over the issue of whether states are inherently security-maximizers (as asserted by defensive realists such as Waltz) or power-maximizers (as asserted by offensive realists such as Mearsheimer), all structural realists insist that states are prevented by anarchy from engaging in cooperative treaties to end war. Structural realists see states’ security-seeking and power-seeking behaviors as being relatively fixed, because of the deterministic role of international anarchy forcing the states to behave like security-maximizers and powermaximizers in a similar manner. Thus, the impact of ideas on state behaviors and power politics disappears in their realist paradigm. In other words, structural realists leave little role for ideas in the international politics because the primary mover is a structural factor, i.e., the anarchic structure of international system itself, as a fundamental cause of international conflict. For this reason, constructivists see structural realism as a largely empty theory, pointing out that the role of international anarchy in structural realism is fixed and self-deterministic.

In particular, structural realism is strongly challenged by the recognition made by constructivists that what has been characterized as structure is really only social fact. Since structure as a social fact is subject to endogenous change, not exogenously given or predetermined, the motivations that it assigns to actors arise from agency first, while maintaining the appearance of structure to the actors. In the case of the international system’s structure (i.e., the distribution of power and polarity), the impact of the structure on states breaks down when confronted with some constructivist understanding that the creation of the state system as a military entity is suggestive of what is perceived to be the appropriate thing to do as a natural outcome of the diffusion of intersubjective cultural and normative understandings among actors in a supportive social and historical context, not as a utilitarian reason for security; therefore, this state system would not initially arise in response to external threats from the anarchic structure of the international system. Based on this viewpoint, states would organize their militaries into armies, navies, and air forces because this is naturally perceived to be the appropriate thing to do over time, rather than because they initially perceive it to be necessary to confront external threats.

However, structural realists may attempt to defend their theory, holding that structural realism as a general theory focuses mainly on explaining the standard pattern of state behaviors that persist across time and space using some structural variables such as distribution of power and polarity, not on explaining whether the state system initially occurred in response to external threats. Despite this potential defense of structural realists, explaining whether the state system arises to confront external threats from the anarchic structure is still important, because the state is an important unit of analysis in their security and power-driven structural theory.

Regarding this issue, Finnemore challenges the common notion that the expansion of bureaucratic institutions, including the state system, results from functional utility, arguing that bureaucratic values have diffused where they encountered a supportive social context.34) In the functional view, the state is because it does, while in the constructivist view suggested by Finnemore, the state does because it is. In this view, since the state system is not a predetermined actor who is necessary to do something, it did not arise in response to external threats. In this context, the state system is also considered another social fact, which is subject to endogenous change, as the system’s structure can be regarded as social fact. Thus, state actors have the abilities to change the characteristics of the anarchic international system into a conflicting (self-help) or a cooperative one (collective security), contrary to the stance of structural realism.

Further, power of ideas such as nationalism, political ideology, and religion fosters international conflict in world politics. The location of power of ideas is in the middle and overlapping ground between individual actors and structure, especially affecting the actors’ identities and interests. However, the predefined and self-deterministic structure in structural realism, which constructs state actors’ identities and interests, is directly linked to the assumption that these actors are automatically compelled to accepting a similar mode of rationality, i.e., seeking security and power maximization, under this structure; therefore, the impact of power of ideas on actors disappears in this structuralist model. Mearsheimer himself concedes the weakness of his structural theory related to the issue of the so-called “power of nationalism,” arguing that in the nineteenth century, the United States refrained from expanding to Mexico and Canada due largely to the rise of these states’ modern nationalism.35) The rise of international terrorism in recent years is also another typical example resulting from power of ideas because the primary motive of international terrorism is closely associated with a hatred of freedom and spreading democracy, which can be considered an ideational factor. However, by leaving little room for ideas in its paradigm, structural realism limits its ability to investigate such complex contemporary phenomena of world politics.

21)Kenneth N. Waltz, “Anarchy Orders and Balance of Power,” in Robert Keohane (ed.), Neorealism and Its Critics (New York: Columbia University Press, 1986), p. 108.  22)Joseph M. Grieco, “Anarchy and the Limits of Cooperation,” International Organization 42-3 (1988), pp. 487-489.  23)Ibid., pp. 98-130.  24)Kenneth N. Waltz, op. cit., pp. 126-128.  25)Ibid., p. 96.  26)Kenneth N. Waltz, Theory of International Politics (Massachusetts: Addison-Wesley, 1979), p. 131.  27)John J. Mearsheimer, The Tragedy of Great Power Politics (New York: W. W. Norton, 2001).  28)Ibid., p. 31.  29)Ibid., p. 20.  30)Ibid., p. 21.  31)Ibid., pp. 269-272.  32)Ibid., p. 166.  33)Ibid., p. 335.  34)Martha Finnemore, op. cit., pp. 328-330.  35)John J. Mearsheimer, op. cit., p. 488.

Modified realists agree with structural realists’ assumption that a significant element contributing to a persistent search for power and security is international anarchy. But for modified realists, “anarchy is a permissive condition rather than an independent causal force,”36) which is in a manner similar to the advocates of classical realism. In this context, anarchy does not imply constant chaos, conflict, or confusion. It simply indicates that there is no “reliable central authority to which they [states] can appeal for protection or the redress of grievances.”37) Therefore, anarchy does not uniformly bring about severe security pressures for all states. Modified realists also refuse the notion of the state as ‘black box’, incorporating the variety of intervening variables such as domestic structures, policymakers’ perceptions of relative power and threats, leaders’ images and personalities, etc. into their paradigm.

When it comes to an intervening variable—like domestic structures, for instance—unlike the existing realist approach that focuses on structural (systemic) pressures on states’ behaviors, a modified realist approach emphasizes the impact of domestic structures on states’ behaviors. From this perspective, this approach includes “the effectiveness of the state’s administrative and political machinery”38) as an important variable to explain states’ behaviors. In fact, various domestic actors, including bureaucratic agencies, interest groups, and lobbyists, can affect the policymakers’ decision-making processes with respect to states’ foreign policy behaviors. However, such decision-making processes can be conditioned by not only structural pressures (realist factors) but especially by the prevailing set of ideas (constructivist factors) as well.

In particular, neoclassical realists,39) as typical modified realists, maintain that relative material power sets the essential limits of a nation’s foreign policy. They note there is no instant or ideal transmission belt connecting material capabilities to foreign policy behaviors. Foreign policy decisions are made by actual political leaders (policymakers), and so it is their perceptions and assessments of relative power that are significant, not just the relative quantities of physical resources available.40) This perceptional variable (political leaders’ perceptions of relative power or their collective beliefs about how to act) at the unit level is an ideational factor, not a material one. This ideational factor can mediate how political leaders and elites respond to structural pressures. In short, this ideational factor is a guidepost that helps to condition how states will pursue security and what they will do with their power in the international system.41)

Classical realism also abandons the causal role played by the anarchic structure of the international system; it focuses instead on human nature (which is close to ideational factors) as a crucial causal force; therefore, it may have room for incorporating the causal power of ideas in the explanations of states’ behaviors. With regard to this issue, J. Samuel Barkin argues that classical realism and constructivism are, to some extent, compatible because a “broad range of theories of human nature ⋯ are compatible with both [classical] realist and constructivist theory.”42) Since constructivism is regarded as “a set of assumptions about how to study world politics” rather than as “a set of assumptions about how politics work,”43) it can be subject to “dialectic between realism and utopianism” (as in E. H. Carr ’s classical realist work The Twenty Years Crisis).44) From this perspective, Barkin believes that a “healthy infusion of realism” (especially classical realism) into contemporary constructivism can help the latter to escape from its biased view, which has been derived largely from its overdependence on idealism and liberalism.45)

I take Morgenthau’s classical realism as a typical example to deal with the issue of potential compatibility and combination between classical realism and constructivism. Morgenthau presented the first principle of political realism as follows: Politics is “governed by objective laws that have their roots in human nature.”46) In Morgenthau’s understanding, human nature rather than anarchic structure lies behind actions in international politics. It helps us open up recurrent nonstate phenomena in modern international relations for study using the presumptions of political realism. Morgenthau also views interest defined in terms of power as necessary to the development of a theory of political realism, domestically and internationally.47)

Further, Morgenthau claims that the condition of exercising power is dependent upon the political and cultural context in which it exists covering all means by which man dominates man ranging from “physical violence to the most subtle psychological domination by which one mind controls another.” In his view, while interests dominate man directly, ideas offer the “image of the world” by which interests are constituted. Indeed, by enhancing the understanding of what power is, by whom it is exercised in the international politics, and how it is constituted, Morgenthau attempts to implicitly integrate the causal power of ideas into the classical realist canon.48)

In particular, the conceptualization of power running along a continuum from physical violence domination to the very subtle psychological domination implies that the phenomena of international conflicts are far more extensive than suggested by structural realism. In other words, power is not the exercise of physical force alone; it is also the domination of man by man through the creation of social orders that confronts actors as structures constrain their actions. Social orders confronting actors are derived from ideas as “images of the world,” as Morgenthau writes, by which interests are constituted. Therefore, the creation of a particular social order that can benefit those who hold power will become the objective of state action.

Indeed, the impact of ideational factors on power politics matters because they can provide a motive for using brute, physical force as means by which man dominates man. Ideational factors in this classical realist tradition can also provide a particular condition to restrain or moderate an exercise of power and a politics with an emphasis on ethics as its core.49) In this context, Morgenthau would observe the three types of state motivation for pursuing power politics as follows: a “policy of the status quo” having a goal of keeping power; a “policy of imperialism” having a goal of increasing power; and finally a “policy of prestige” having a goal of demonstrating power.50) Moreover, Morgenthau stressed the determining choices of political leaders in a given situation, and those choices in turn showed their particular character, vision, and ethical commitments.51) This approach to the leaders’ decisions can also be associated with ideational factors. In sum, Morgenthau’s classical realism implicitly accommodates the causal power of ideas in the power politics, albeit with a somewhat different interpretation than that provided by constructivists.

Various modified realists attempt to reach back to the “richness of the tradition of political realism” represented by Morgenthau.52) In the modified realist understanding, power is the foundational characteristic of international politics, but it needs to be seen as more than physical force or materialist concept of power alone. In particular, they implicitly concede the important role that ideational factors play in the levels of policymakers and states rather than in the level of structure, in order to more fully understand the inherent nature of power and its effects on modern international relations.

Robert Jervis’s work is a typical example of modified realism incorporating ideational factors.53) He argues that whether defensive weapons and strategies can have a distinction from offensive ones is an important factor affecting the degree of the security dilemma and the likelihood of war. In this view, the distinction between defensive and offensive ones is not dependent entirely on military technology and strategy per se. Rather, ideas matter a great deal in Jervis’s theoretical framework, because they form the basis by which states perceive given technologies and strategies as offensive or defensive.

Since ideas are considered intersubjective ones, this may substantially decrease the potential risk of conflict by providing shared meaning that allow states to reduce uncertainty of opposing states’ intentions. Thus, if ideas of what is perceived to be offensive and what is perceived to be defensive are really intersubjective, they allow states to avoid conflict arising from misperception and miscommunication as an indicator of lack of intersubjective understanding, rather than from states’ malicious intentions themselves. In short, Jervis’s attempt to implicitly add the impact of ideas to the explanation of international politics is a considerable improvement over the strains of structural realism.

Meanwhile, Colin S. Gray maintains that “the material approach to defense policy is ever prone to perpetrate the fallacy of equating threat with capability.”54) Considering Gray’s argument, whether war is waged is not necessarily driven by a significant change in the opposing states’ military technologies and capabilities alone. This attempt to emphasize the difference between threat and capability is closely associated with the balance of threat theory represented by Stephen Walt.55) Walt’s balance of threat theory attempts to modify structural realism by separating power from threat. Walt determines four criteria by which states evaluate another state’s threat: a state’s aggregate strength (economy, population, and size), its geographic proximity, its capabilities for offense, and its offensive intentions.56)

In Walt’s view, whether states have offensive intentions is a crucial factor affecting the type of alliance choices and the likelihood of war. Walt simply put that state actors “balance against threats rather than simply against power.”57) For example, many states during the Cold War aligned with the United States rather than the Soviet Union because the Soviet Union was perceived to be posing the more significant threat despite its limited capability compared to that of the United States. Walt himself explains the real reason for many states not to balance against stronger power, the United States, noting that “perceptions of [offensive or defensive] intent are likely to play an especially crucial role in alliance choices.”58)

A neoclassical realist Schweller indirectly supports Walt’s balance of threat theory, arguing that security dilemma is based on the existence of predator states (i.e., revisionist states) with offensive intentions, not on the anarchic structure itself.59) Schweller challenges structural realism, arguing as follows: “Predatory states motivated by expansion and absolute gains, not security and the fear of relative losses, are the prime movers of neorealist theory [i.e., structural realism]. Without some possibility of ⋯ [the] existence [of predatory states], the security dilemma melts away.”60) This logically means that international cooperation and alignment among nonpredatory states with defensive intentions are more probable. Further, by arguing that states have various interests, not the same and pre-given interests that structural realists assume, Schweller allows the possibility that states can change their interests affected in part by changes in ideas, that is, changes in intersubjective understandings of interests in various social and historical circumstances.61)

Notwithstanding the indirect support of Schweller to Walt’s theory, Christopher Layne directly refuses Walt’s balance of threat theory especially related to the issue of the US unipolarity in the post-Cold War era.62) Layne argues that because “the United States is also an expansionist state that seeks to increase its power advantages and to extend its geographical and ideological reach,”63) it is difficult to differentiate power from threat.64) However, regarding the preventive war against Iraq, while second-tier great powers like France, Germany, and Russia strongly criticized the lack of legitimacy of the war carried out by the United States, they would not believe that they were militarily threatened by the United States because they perceived US intentions to be defensive, not offensive, at least toward them.

Considering the role of ideas implicit in Walt’s balance of threat theory, the level of threats perceived by opposing state’s leaders may be inherently intersubjective, meaning the product of identity and rules attached to the states’ particular behaviors in a social and historical context.65) This conceptualization can also be linked to Wendt’s famous statement that the United States is less afraid of 500 British nuclear weapons, while they are more afraid of the five North Korean nuclear weapons,66) although modified realists and constructivists may have somewhat different interpretations of this statement.

With regard to the level of intersubjective threat perceptions, we may infer that even though North Korea’s power was stronger than that of Iraq, US policymakers may perceive that North Korea was less threatening than Iraq comparing North Korea’s past behaviors with those of Iraq. For example, the Bill Clinton administration in the United States perceived that Iraq was the most dangerous rogue state in the world. On 26 June 1993, Clinton criticized Saddam Hussein for the issue of significant threat posed by his regime:

In the Clinton administration’s view, Iraq would be quite willing to use weapons of mass destruction (WMDs) on other countries and even its own people, but the same perception may be not prevalent regarding North Korea’s nuclear weapons issue. On 21 September 1993, in his speech at Johns Hopkins University, President Clinton’s Security Advisor Anthony Lake directly referred to Iraq as members of backlash states along with Iran, but he did not mentioned North Korea as one of the states threatening the United States.68) Even before the nuclear crisis, Al Gore, who soon became US vicepresident, positively assessed Kim Il-sung regarding his efforts to include capitalist structures in some regions of his country as a “free trade zone.”69)

Based on this viewpoint, many US policymakers have perceived to some extent that North Korea’s attempt to develop a nuclear weapons program was caused mainly by its defensive intentions like fear of its security rather than by offensive intentions such as invading South Korea; therefore, their top policy preference toward North Korea has focused on a diplomatic solution or an economic sanction rather than on military action, although this interpretation cannot fully explain the motives behind the different policy choices of the United States toward Iraq and North Korea. In this respect, actors (such as political leaders and elites) can alter their strategies or even their most basic identities and preferences based on their learning, that is, particular lessons from their experiences.70) This approach concerns the constructivist stance, because it attempts “to identify causal connections between ideas [i.e. intersubjective understandings of each other’s intentions] and policy outcomes.”71) This approach can also be linked to a modified realist theory like Walt’s balance of threat theory.

In particular, for neoclassical realists, the issue of policymakers’ perceptions of relative power as a component of ideational factors is a very important intervening variable affecting the likelihood of conflict and cooperation. William Wohlforth argues that “if power influences the course of international politics, it must do so largely through the perceptions of the people who make decisions on behalf of states.”72) In this context, Wohlforth modified structural realism by comparing the Soviet and American leaders’ perceptions of powers during the periods of the Cold War in order to determine “whether the two sides’ views of power in world politics were related to the course of their prolonged mutual antagonism.”73) These perceptions are strongly related to the creation and change of ideas affecting the two superpowers’ behaviors.

Similarly, Keith L. Shimko attempted to modify the existing realism, holding that the effects of hard-line or soft-line state images, derived from perceptions of each other’s policymakers, can shape policy preferences at individual policymakers’ level.74) For instance, if soft-line images prevail between policymakers in the opposing states, ideas constituting common interests that can serve as the foundation for agreement also prevail, because the conflict is no longer seen as a “zero sum game.”75) In Wohlforth’s and Shimko’s understandings, anarchy is important, but not a determinant affecting competition and cooperation between the superpowers. Rather ideational components of power such as leaders’ perceptions of opposing states’ powers and perceptions of each other’s policymakers (the so-called state images) are a crucial factor affecting state behaviors and power politics.

Meanwhile, James D. Fearon seizes upon the role of information asymmetries as a key factor in explaining why states as rational actors resort to war even where both parties would prefer the alternative.76) Fearon implicates lack of intersubjective knowledge between state actors as a fundamental source that triggers inefficient conflict, reducing the possibilities of choosing the option of mutual preference.77) In his view, international conflict was caused by the lack of, not impossibility of, mutual information, i.e., intersubjective knowledge, between state actors rather than by anarchic structure, as structural realists assume, imposing the impossibility of intersubjective knowledge on the state actors. Although the issue of lack of mutual information as sources of conflict represented by Fearon78) suggests that the likelihood of conflict in the modified realist world is still greater than that in the constructivist one, we nonetheless need to pay attention that this issue—the degree of sharing information between states—is closely associated with ideas as an underlying source of cooperation and conflict.

While structural realism, as this study has addressed in the previous section, leaves little role for ideas in international politics, this section finds that some classical realist and various modified realist theories have abilities to add the role of ideas to their explanations of state behaviors and power politics. In particular, by implicitly incorporating ideational factors (such as political leaders’ perceptions of relative power) in their theoretical models, modified realists (especially neoclassical realists) try to explain particular states’ motivations and behaviors, i.e., the circumstances under which a particular state forms an alliance with other states or when it chooses to cooperate or expand.

Meanwhile, two other scholars note, “Although material influences have to be relayed to states’ behavior via ideational forces, ultimately no ideational factors can operate without underpinning material factors.”79) Therefore, we should also pay attention to the possibility that if ideas ignore the impact of relative power on political leaders’ decisions and states’ behaviors, then they have the potential to yield disappointing outcomes that lead to the delegitimization of these very ideas. From this perspective, this study stresses that ideational forces and structural forces (i.e., distribution of relative power in the anarchic international system) must be best understood as complementary to, not competing with, each other. This combination of ideas and power can provide us with not only more case-sensitive but also more generalizable explanations of states’ behaviors in the international system.

Although it is still true that the role of ideas has been given little explicit observation in the realist literature, its presence is implicit especially in much of the modified realists’ works, holding the promise of so-called “constructive realism.” In sum, as the term “constructive realism” suggests, some classical realist and especially modified realist theories have enough room for accommodating the role of ideas in their realist repertoire, enhancing the understanding of complex phenomena of modern international relations.

36)Stephen M. Walt, “The Enduring Relevance of the Realist Tradition,” in Ira Katznelson and Helen V. Milner (eds.), Political Science: The State of the Discipline (New York: W. W. Norton, 2002), p. 211.  37)Joseph M. Grieco, “Realist International Theory and the Study of World Politics,” in M. Doyle and J. B. Ikenberry (eds.), New Thinking in International Relations Theory (Boulder, CO: Westview Press, 1997), p. 164.  38)Christopher Layne, “The Waning of U.S. Hegemony—Myth or Reality?” International Security 34-1 (2009), p. 164.  39)As Gideon Rose has cogently summarized, neoclassical realists hold “that the scope and ambition of a country’s foreign policy is driven first and foremost by its place in the international system and specifically by its relative material power capabilities. This is why they are realist. They argue further, however, that the impact of such power capabilities on foreign policy is indirect and complex, because systemic pressures must be translated through intervening variables at the unit level. This is why they are neoclassical.” Gideon Rose, “Neoclassical Realism and Theories of Foreign Policy,” World Politics 51-1 (1998), p. 146.  40)Ibid., pp. 146-147.  41)Nicholas Kitchen, “Systemic Pressures and Domestic Ideas: A Neoclassical Realist Model of Grand Strategy Formation,” Review of International Studies 36-1 (2010), pp. 117-143; Jonathan Monten, “Primacy and Grand Strategic Beliefs in US Unilateralism,” Global Governance 13-1 (2007), pp. 119-138.  42)J. Samuel Barkin, “Realist Constructivism,” International Studies Review 5-2 (2003), p. 330.  43)Ibid., p. 338.  44)Patrick Thaddeus Jackson et al., “Bridging the Gap: Toward A Realist-Constructivist Dialogue,” International Studies Review 6-2 (2004), p. 337.  45)Ibid., pp. 325-342.  46)Hans J. Morgenthau, Politics Among Nations (New York: Wiley & Sons, 1948), p. 4.  47)Ibid., p. 5.  48)Ibid., p. 8.  49)Michael C. Williams, The Realist Tradition and the Limits of International Relations (Cambridge: Cambridge University Press, 2005).  50)Hans J. Morgenthau, op. cit., p. 39.  51)Richard N. Lebow, The Tragic Vision of Politics: Ethics, Interests and Orders (Cambridge: Cambridge University Press, 2003).  52)Robert Gilpin, “The Richness of the Tradition of Political Realism,” in Robert Keohane (ed.), Neorealism and Its Critics (New York: Columbia University Press, 1986), p. 319.  53)Robert Jervis, “Cooperation under the Security Dilemma,” World Politics 30-2 (1978), pp. 167-214.  54)Colin S. Gray, Weapons Don’t Make War: Policy, Strategy, and Military Technology (Kansas: Kansas University Press, 1993), p. 29.  55)Stephen M. Walt, “Alliance Formation and the Balance of World Power,” International Security 9-4 (1985), pp. 3-43.  56)Ibid.  57)Quoted in Paul Schroeder, “Historical Reality versus Neo-Realist Theory,” International Security 19-1 (1994), p. 119.  58)Stephen M. Walt, The Origins of Alliances (Ithaca and London: Cornell University Press, 1987), p. 25.  59)Randall L. Schweller, Deadly Imbalances: The Tripolarity and Hitler’s Strategy of World Conquest (New York: Columbia University Press, 1998).  60)Ibid., p. 119.  61)Ibid., p. 22.  62)Christopher Layne, “The Unipolar Illusion Revisited: The Coming End of the United States’ Unipolar Movement,” International Security 31-2 (2006), pp. 7-41.  63)Ibid., p. 13.  64)Ibid., p. 20.  65)Peter Howard, “Why Not Invade North Korea? Threats, Language Games, and U.S. Foreign Policy,” International Studies Quarterly 48-3 (2004), pp. 811-812.  66)Alexander Wendt, “Constructing International Politics,” International Organization 20-1 (1995), p. 73.  67)Bill Clinton, “Containing Iraq,” Address to the Nation, The White House, Press Briefings and Speeches by the Principals, 26 June 1993.  68)Anthony Lake, “From Containment to Enlargement,” speech at the School of International Studies, Baltimore, Johns Hopkins University, 21 September 1993.  69)Al Gore, “Global Climate Protection Act,” Congressional Record (26 March 1992).  70)Richard N. Lebow, “The Search for Accommodation: Gorbachev in Comparative Perspective,” in R. N. Lebow and T. Risse (eds.), Understanding the End of the Cold War (Baltimore, MD: Johns Hopkins University Press, 1995); Stephen G. Brooks and William C. Wohlforth, “Power, Globalization, and the End of the Cold War: Reevaluating a Landmark Case for Ideas,” in J. S. Levy and G. Goertz (eds.), Explaining War and Peace: Case Studies and Necessary Condition Counterfactuals (London and New York: Routledge, 2007), p. 198.  71)Adreas Bieler, “Questioning Cognitivism and Constructivism in IR Theory: Reflections on the Material Structure of Ideas,” Politics 21-2 (2001), p. 94.  72)William Wohlforth, The Elusive Balance: Power and Perceptions During the Cold War (Ithaca and London: Cornell University Press, 1993), p. 2.  73)Ibid., p. 1.  74)Keith L. Shimko, Images and Arms Control: Perceptions of the Soviet Union in the Regan Administration (Ann Arbor, MI: University of Michigan Press, 1991), p. 242.  75)Ibid., p. 244.  76)James D. Fearon, “Rationalist Explanation for War,” International Organization 49-2 (1995), pp. 379-414.  77)Ibid., p. 385.  78)Ibid., pp. 379-414.  79)Shiping Tang and S. R. Joey Long, “America’s Military Interventionism: A Social Evolutionary Interpretation,” European Journal of International Relations (May 2011, online ed.).

As shown in this study, some classical realist and especially various modified realist theories implicitly address the important impact of ideas on power politics and state behaviors. In doing so, they provide us with ideas not only as a transmission belt connecting material power to foreign policy outcomes but as an intervening variable conditioning their relationships as well. Thus, these realist theories permit greater flexibility in explaining the reasons for which a particular state seeks to increase not only its power and security but even the possibility of its cooperation with other states as well. Therefore, these theories can help realists to escape from the strictures of rationalist theories, especially structural realism. In fact, the so-called ‘threelevels of analysis’ (i.e., system, state, individual level) of some classical realists’ have provided more sophisticated and deep explanations on what causes war. For example, Thucydides concluded that the cause of the Peloponnesian War was the growth of the power of Athens and the fear it caused in Sparta, even though he also emphasized the importance of domestic political factors and leaders’ perception as well.80) However, the Yale classicist Donald Kagan argues that the Peloponnesian War was not inevitable. More specifically, Kagan argues that the war was not caused by impersonal forces but by bad decisions in difficult circumstances. Instead, he insists that even though the Greek structure of BC 431 made war highly probable, there had been many opportunities to avoid the war.81) That means the immediate or precipitating causes played a more important role in the occurrence of the war. In short, according to Kagan, political culture and personalities made a difference; even they work within limits set by the larger structure. This is why so many classical realists insist that World War I and World War II were not inevitable and three-levels of analysis are necessary.82) As a matter of fact, classical realists and various modified realists believe that parsimony of structural realism is only one of the criteria by which we judge the adequacy of theories, and that neorealist structure provides only a partial explanation on most cases of war history. Constructivist attention to ideational factors reminds us not to be blind to social change. It also may provide us with some useful orientation of development for realist theories.

However, the rise of international terrorism in recent years, which represents a nonstate, cross-border, network-based phenomenon targeting of unspecified civilians, challenges some important assumptions of realism (even including those of modified realist theories). In other words, by emphasizing the role of nonstate actors in the international system, the study of international terrorism directly contradicts the realist assumptions that international conflicts come from the role of international anarchy (structural realism), predatory states, and states’ offensive intentions (modified realism). In particular, the rise of Islamic fundamentalism (ideational factor) combined with terrorist violence (nonstate factor) springs to mind, where the influenced parties, especially those in the Middle East, view the cultural transformation brought by the adoption of US-led Western values as an attack on their very social existence. This phenomenon causes a complex, new kind of security dilemma in contemporary world politics.

The above phenomenon is derived not from the fact that Islamic states or Muslim people are uniquely aggressive, but from the spread of modern Western values, which increases the existential threat to the identities held by many in Islamic societies. Some view their domestic social order as threatened, as it seems to resemble more and more that of the secular West, which imposes domination not by the use of physical force against Islamic states but instead against their ideational framework created by their unique social and historical process, constituting important cultural values of their domestic societies. From this perspective, the modified realist theories need to be more elaborated in order to better account for such complex ideational components of power involved in the recent phenomenon of international terrorism.

To make a better realist theory—a so-called “constructive realism”—one should better explain the fundamental nature of power and recent important phenomena in international politics. Although this attempt to secure greater explanatory power may undermine the parsimony of traditional realism (especially structural realism), it is still important because careful theoretical work can not only offer a more detailed picture of contemporary world politics but also assist policymakers in understanding what is needed to achieve a specific result. In order to enhance the understanding of ideational components of power and of complex motives of recent international terrorism that is generating a new security dilemma in world politics, efforts must be made to more explicitly integrate ideational factors into the realist canon.

80)Thucydides, History of the Peloponnesian War, trans. by Rex Warner (London: Penguin Books, 1954).  81)Donald Kagan, The Outbreak of the Peloponnesian War (Ithaca, NY: Cornell University Press, 1969), pp. 31-56; J. Joseph Nye and David A. Welch, Understanding Global Conflict and Cooperation: An Introduction to Theory and History (New York: Longman Press, 2011), pp. 86-100 and pp. 112-127.  82)Ibid.