What is now colloquially termed the interwar period has long attracted both scholarly and popular attention in that it spanned the First and Second World Wars and saw a concatenation of political turmoil, economic disruption, social upheaval, and ideational change. A highly popularized interpretation of the period is that the Second World War as the deadliest global conflict in history was a corollary of the preceding world war.¹ The fragile and incomplete peace agreement made in the wake of World War I, the popular argument goes, worsened the already unstable international order by fueling nationalist backlash against the settlement in Germany. The interwar period also saw the Great Depression as a new kind of global recession that occurred when the gold standard was already malfunctioning and yet economic nationalism was on the rise. As a result of wartime mobilization during 1914-1918, organized labor became more assertive, which strengthened the class consciousness of the middle classes in many countries, especially those characterized as “aliberal societies” (Luebbert 1991, 159). Social cleavages, both preindustrial and industrial, were catapulted into political struggle in economically hard times. In response to this complex situation arose a variety of heterodox policy ideas against nineteenth-century laissez-faire with national variations from the New Deal to Social Democracy to National Socialism (Gourevitch 1986).

Edward Hallett Carr (1939; 1946) characterized this disturbingly transformative period as the “twenty years’ crisis,” which connotes the historical distinctiveness of the times as well as the inextricable links between the two world wars. As we shall see in the next section, Carr gives a very insightful account of what constituted the interwar crisis. As the term crisis is used throughout this article, giving a definition of it is in order. Following Antonio Gramsci (1971),² I define a crisis as the state of affairs in which an old arrangement crumbles but a new one is not yet in place. Crisis of the international system, therefore, is tantamount to an unraveling of the status quo with dim prospects for reequilibration. The realist tradition tends to pay disproportionate attention to the political or security side of crisis. Before 1914, the primacy of politics over economics was evident particularly in the relations among great powers. Yet at the same time political regime type and/or “social purpose” (Ruggie 1982) at the domestic level had shaped the way wars were initiated and terminated even during the era of absolutism to a certain degree. Crisis has always been a mixture of political, economic, social, and ideational changes. Then what makes distinct the interwar period as a case of crisis in international relations? The main thrust of this article is that “contested social orders” (Skidmore 1997) at the domestic level had a very complicated impact on great power rivalry between the two world wars, presenting themselves as serious alternatives to the pre-1914 system that combined the balance of power with economic interdependence not backed by broad-based domestic coalitions.

This line of argument contrasts markedly with much of realist international relations (IR) scholarship which in its theoretical explanation of the interwar crisis has focused on an obviously important but narrow question: why the timeless principle of the balance of power did not work during the interwar years, culminating in the most destructive war in human history, World War II. If the balance of power had been at play in a normal way, the realist argument goes, there would have been no appeasement toward Nazi Germany. The realist logic of the balance of power, as elegantly formulated by Kenneth Waltz ([1979] 2010), allows us to understand the structure of international security, but it lacks subtleties and nuances necessary for figuring out the complex nature of the interwar crisis. As Michael Howard (1977, ix) wrote, “… to abstract war from the environment in which it is fought … is to ignore a dimension central to the understanding, not simply of the wars themselves but of the societies which fought them.” This warning is echoed by a recent author (Anievas 2014, 215) who said, “The erasure of social structure from the study of IR has incapacitated theoretical understandings and explanations of the two world wars.” The interwar crisis was much more than a prelude to the Second World War. I argue that the balance of social forces at the domestic level shaped the different paths out of the nineteenth-century liberal order and that the interwar crisis was largely due to the high degree of incongruence in social orders among great powers. Liberal social orders of the United States, Britain, and France affected the “satisfied”³ great powers’ uncoordinated, belated policy choices in response to two different kinds of threat from fascism and communism. Illiberal social orders of Germany, the Soviet Union, Italy, and Japan shaped the “dissatisfied” great powers’ aims to replace the crumbling liberal international order. Though this article is not about the causes of World War II, any attempt to probe into them would benefit from taking social orders seriously.

Relatedly, a fuller understanding of the twenty years’ crisis also requires us to go beyond the unnecessary divide between political economy and security studies within IR scholarship (Kirshner 1998). It was mercantilists rather than liberals who appreciated the importance of political economy in figuring out the structure and change in security relations among great powers. The mercantilist reasoning is composed of two elements: (1) power and plenty are fungible; and (2) the pursuit of power determines the organization of economic activities. In an effort to dismantle the mercantilist barriers to advancing the economic interests of the emergent middle class, liberal thinkers asserted the semblance of the economy (or markets) to nature, giving support to the idea of laissez-faire capitalism. The liberal critique of mercantilism generated the myth of “the self-regulating market” in eighteenth-century Europe, and it achieved an orthodoxy status during the nineteenth century (Polanyi [1944] 1957). Much of liberal IR scholarship is based on the nineteenth-century notion of society analytically separate from the state. Its bottom-up view allows us to take into account societal variables in explaining state behavior in international relations. But this liberal approach also tends to reduce our sensitivity to the larger context of societal factors. Given the affinity between mercantilism and realism, it is an irony that mainstream IR research has been conducted by realists who do not care much about the liberal separation of security and political economy and yet commit the same sin.⁴

Paradigmatically speaking, this article is an attempt to retain the (classical) realist kernel and complement it with a focus on the characteristics of domestic political economies which are conceptualized here as “social orders” (Skidmore 1997).⁵ I have no intention to provide another vindication of the neoclassical realist manifesto by adding more domestic variables to the conventional equation. Instead, I argue that the realist tradition, particularly its classical version which is best exemplified by Carr, has much more in common with what Robert W. Cox (1986) called “critical theory” that “focuses on the development of various state forms in response to changes in the way social forces relate to production, and in response to changing world orders” (Leysens 2008, 3). As a reinterpretation of classical realism through the lens of critical theory, my approach falls under the rubric of “critical realism.”⁶

My argument proceeds in five sections. I start with an examination of Carr’s account of what constitutes the crisis between the two world wars. Then I look at the realist perspective on the balance of power as a linchpin of international order by comparing Robert Gilpin, John Mearsheimer, and Randall Schweller. The latter’s neoclassical realist twist on an otherwise structuralist account of the interwar period is keenly noted. Yet Schweller’s important study turns out to be a reminder of the need to take social orders more seriously than some previous authors who paid insufficient attention to domestic factors. Thus, I bring in the contested social orders approach to the interwar crisis by focusing on the works of Karl Polanyi and John Ruggie as well as David Skidmore and Sandra Halperin. In doing so I also provide the historical context in which liberal and illiberal states responded to the prewar order’s demise in different ways. Then I present a critical realist typology of international order that takes the number of poles and the degree of social order compatibility as two dimensions of great power rivalry, putting the interwar period in a comparative-historical perspective. I conclude with a summary of the argument, a brief discussion of my typology’s applicability to a wider range of historical and contemporary cases, and a caution about the use of historical analogies.

In The Twenty Years’ Crisis, originally published in 1939,⁷ Carr raised an important question about the difference between the nineteenth century’s international order and the early (or first part of) twentieth century’s. Graham Evans (1975, 80) cogently argues that Carr has captured the misfit between the nineteenth-century notion of harmony of interests and international relations after World War I. The Benthamite idea of liberal internationalism could not be realized in the aftermath of the first total war. The crucial factors were the emergence of mass democracy and the establishment of the first socialist regime in Russia. Globalization or economic openness was a structural condition that sowed the seeds of class and sectoral conflict (Brawley 1997; Hiscox 2001). But it was not a sufficient condition for the international order’s collapse and eventually the outbreak of World War II. The intellectual bankruptcy of the Benthamite idea after the global conflagration gave liberals justifications for hammering out an institutional solution to international security. As we all know, realism emerged as a counterattack against liberals by denigrating the latter as idealists during and after World War II. And the predominance of realism was achieved often at the expense of due appreciation of the social dimensions of world politics.

Despite his pivotal role in establishing the realist paradigm, a close reading of The Twenty Years’ Crisis shows that Carr was keen on the social dimensions of world politics that became more distinct after World War I. He was among the very few who appreciated the links between interstate relations and the evolution of the capitalist economy (Goldfischer 2002, 699). For many scholars of international political economy (IPE), especially those in the liberal tradition, the demise of international economic order during the 1930s was considered as a root cause of another global war. Autarky was an aberration to much of IPE scholarship, not only liberal but also realist. For Carr, autarky was a rational response to the increasingly interdependent world economy. “Internationally, the consequences of absolute laissez-faire are as fantastic and as unacceptable as are the consequences of laissez-faire within the state. In modern conditions the artificial promotion of some degree of autarky is a necessary condition of orderly social existence” (Carr 1946, 121). Autarky was one of various illiberal policy packages that were employed by great powers, both satisfied and dissatisfied, in addressing the disconnect between increasingly centralized domestic economies and the then drifting, nonhegemonic world economy. Foreign trade was also actively sought as a means of state power during the interwar period (Hirschman [1945] 1980, 34-40). “Purchasing power had become an international asset; and the fact that price was no longer the dominant factor (Germany made most of her purchases in South-Eastern Europe at rates above world prices) put the purchaser and not the producer in a position to call the tune” (Carr 1946, 129). But Carr did not further develop his argument on the varieties of national responses to the changing environment in The Twenty Years’ Crisis.

This job was done in The Conditions of Peace (1942), and hereafter I summarize his account of what constitutes the crisis between the two world wars. For Carr, the essence of the twenty years’ crisis lies in the inability of the nineteenth-century liberal order, domestic and international alike, to deal with the military, political, and economic changes unleashed since 1914. He describes the peacemakers of 1919 including Woodrow Wilson as the “reactionaries” who wanted to restore the pre-1914 order by institutionalizing nineteenth-century liberal doctrines in the form of the League of Nations. Satisfied great powers “in search of stability” (Maier 1987) seemed to dominate the scenes of world politics after 1919, but beneath the appearances lay the undercurrent of revolutionary change. Dissatisfied great powers such as Nazi Germany and the Soviet Union were much keener on the “great transformation” than the victors who drafted the fragile peace agreement of 1919. World War II can be attributed to the eruption of those dissatisfied great powers’ ambition to remold the international order as they believed it should be or they wanted it to be.

The three crises characterizing the interwar period, according to Carr (1942, 14), are “the crisis of democracy, the crisis of national self-determination, and the economic crisis.” First, the crisis of democracy reflected, most of all, the mismatch between rapidly expanded political rights in the form of universal suffrage and the socioeconomic conditions of the masses. Liberal democracy, which had been a polity “of groups of privileged persons enjoying equal rights among themselves, but not sharing those rights with other members of the community” (Carr 1942, 20), found it overwhelming to accommodate the demand of “organized economic power” (Carr 1942, 22). There were national variations on the extent to which organized labor was integrated as a legitimate component of social order. Britain and the United States were successful in coopting “the most highly paid and securely employed grades of labour” (Carr 1942, 25), while in Germany and Japan before 1914 the military had a strong presence and thus organized labor could not establish itself as part of the political regime. Disenchanted with the façade of political rights, organized interests in illiberal states flocked en masse to the political machines of fascists or communists in search of socioeconomic security.

Second, the crisis of national self-determination is directly related to Woodrow Wilson and the League of Nations, but its root cause lay in the nineteenth-century idea of nationalism. The principle of “one nation, one state” was a reasonable solution to frequent but not system-disrupting interstate disputes during the period of 1815-1854 when great power rivalry was managed by the Concert of Europe. Furthermore, the notion of national self-determination was an outgrowth of “the idea of democracy” (Carr 1942, 39). When the peacemakers of 1919 applied this seemingly noble idea to the independence of weak states which were part of the defeated empires, it meant the proliferation of sovereign nations with little resources to cope with the changing environment of the domestic and international political economy. It was a grave mistake for Wilson and his fellow utopians to fail to realize that “self-determination is not a right of certain recognized and pre-determined nations, but a right of individual men and women, which includes the right within certain limitations to form national groups” (Carr 1942, 49). The death blow to the utopian project was “developments of military technique” (Carr 1942, 52) which made it unfeasible to maintain the independence of small states by means of concert diplomacy.

Third, the economic crisis during the interwar period also reflects the inertness of conservatism in response to structural changes underway. While the nineteenth-century idea of liberal capitalism was constructed on the primacy of individuals, quantitative wealth, and production, the world after 1914 saw the growing importance of collectivities, qualitative welfare, and mass consumption. Unlike the teachings of classical economists, the central role in the economy was played by two kinds of bureaucratic organizations: big government and big business. This change toward monopoly, public and private, was an outcome of “the development of specialised mammoth industries requiring enormous capital investment and a mass army of labour, both of them incapable of rapid and frictionless transference to meet changing demand” (Carr 1942, 72). Welfare and consumption are related to each other because both reflect the demands of organized labor. Providing decent levels of welfare programs and stable, well-paying jobs became more crucial to the health and duration of political regimes than creating more wealth and increasing production.

Now I go back to Carr’s The Twenty Years’ Crisis as a starting point where he suggested the possibility of critical realism. Unlike the title, Carr’s magnum opus is not a book solely dedicated to analyzing the tumultuous two decades after the First World War. In it Carr laid the foundation for studying world politics as a scientific endeavor—hence the subtitle An Introduction to the Study of International Relations —and the book is still narrowly characterized as a classic text of the realist canon. Doubtless the book is one of the first realist attacks on “utopianism”⁸ as the dominant idea which shaped the outlook of the peacemakers of 1919. But Carr is a very complex thinker whose works cannot be subsumed under the general classification of realism. Indeed, he devoted one chapter to pointing to the “limitations of realism” (Carr 1946, chap. 6). “Consistent realism excludes four things which appear to be essential ingredients of all effective political thinking: a finite goal, an emotional appeal, a right of moral judgment and a ground for action” (Carr 1946, 89). When seen in association with the analysis in The Conditions of Peace, it can be said that Carr distinguished dissatisfied from satisfied great powers in terms of the four ingredients. Revisionist challengers to the crumbling liberal international order could make more progress than status quo powers in consolidating their domestic regimes and projecting their new illiberal ideas onto the international arena.

It was Carr’s acute observation of domestic political-economic changes during the interwar period that has made his realist thinking so distinctive from later scholarly accounts of what happened in the 1920s and 1930s and why, particularly those placing primary—sometimes disproportionate—emphasis on the distribution of material power at the systemic level. We now turn to a discussion of limitations of mainstream realist views on the interwar crisis.

In this section I examine three realist works that explain an unraveling of the international order from the perspective of balance-of-power theory. Gilpin (1981) advances a general theory of international political change by focusing on the question of what drives disequilibrium in the international system, sometimes opening the pathway to hegemonic wars. Mearsheimer (2001) provides an “offensive realist” account of great power politics, particularly that in Europe of the past few centuries. Schweller (1998) offers a revised version of structural realism in an effort to explain the causes of World War II. The focus here is on Schweller’s explanatory scheme rather than Gilpin’s and Mearsheimer’s for two reasons. First, Schweller pushed the structural realist perspective on the balance of power further in a way that redresses the mismatch between the conventional logic and historical realities. Second, his work, unlike those of his two predecessors, directly addresses the interwar period. Before scrutinizing his model, let me turn to Gilpin and Mearsheimer first.

Gilpin is widely acknowledged as a leading realist scholar who provided a general theory of hegemonic wars and international political change. Yet at the same time he was one of the few early IR scholars who pioneered in integrating security and political economy issues in explaining changes in the international system. Indeed, economic aspects of state power take the center stage in his 1981 book. The gist of Gilpin’s argument is: “The most important factor for the process of international political change is not the static distribution of power in the system (bipolar or multipolar) but the dynamics of power relationships over time. It is the differential or uneven growth of power among states in a system that encourages efforts by certain states to change the system in order to enhance their own interests or to make more secure those interests threatened by their oligopolistic rivals” (Gilpin 1981, 93). In short, Gilpin wanted to advance a dynamic theory of world politics, focusing attention on the changing distribution of capability in the system. His theory of hegemonic war made a very important contribution to the literature of cycles of empires and hegemony by looking closely at the “components of the international system” (Gilpin 1981, 186).

Although Gilpin’s 1981 book does not deal with the interwar period in particular, his theory includes great insight that can be used in understanding the twenty years’ crisis. Hegemonic war such as World War II is caused by “disequilibrium in the international system” which is an outcome of “increasing disjuncture between the existing governance of the system and the redistribution of power in the system” (Gilpin 1981, 186). Dissatisfied great powers such as Nazi Germany and Imperial Japan wanted to replace the existing liberal order as an institution with an illiberal world polity of their own. Furthermore, Gilpin places an emphasis on the “interdependence of national economies” (1981, 219) as a “disruptive factor in international relations” (1981, 221). While Gilpin’s work is more theoretical than Carr’s, both authors stopped short of explicitly advancing an early version of the contested social orders approach.

As an offensive realist, Mearsheimer (2001) provides a general theory of great power politics, focusing attention on the experience of Europe during the period of 1792-1990. His argument is straightforward: “multipolar systems which contain an especially powerful state—in other words, a potential hegemon—are especially prone to war” (2001, xiii). So is his measure of polarity. “What matters most is the number of great powers and how much power each controls” (2001, 337). With this cardinal rule he categorizes historical periods of world politics into three kinds of power distribution: bipolarity, balanced multipolarity, and unbalanced multipolarity. The interwar years, which spans from 1919 through 1938 in his periodization,⁹ is characterized as “balanced multipolarity” in that “there was no potential hegemon in Europe during these two decades” (2001, 354). Mearsheimer has little to say about the interwar crisis per se beyond this point. Then why is his work discussed here? For such a parsimonious theory as Mearsheimer’s provides a yardstick by which to evaluate the difference neoclassical realism, as exercised by later authors like Schweller, has made in IR scholarship.

International relations between the two world wars remain a puzzle among students of world politics. In the words of Hajo Holborn (1951, x), “Actually, no world-wide security system came into existence after 1919; yet only the façades of a European system remained standing. In World War II, … the collapse of the traditional European system became an irrevocable fact.” The balance of power, a linchpin of nineteenth-century (or belle époque) international relations, did not work, at least in the traditional sense of the term. The result was the rapid ascendance of Nazi Germany as a revisionist state during the latter half of the 1930s and the outbreak of World War II. Schweller (1998) provides a theoretically less parsimonious but historically more accurate model for explaining what he calls the “deadly imbalances” in power distribution among major states.

Figure 1 represents general agreement among scholars on the relationship between polarity and system stability. It is “curvilinear, not monotonic” (Schweller 1998, 44), which is largely due to the distinctive nature of tripolarity. Even those who do not subscribe to the realist canon would agree that tripolarity is prone to armed conflict among great powers comprising an international system. What distinguishes Schweller from other balance-of-power theorists is that he pays theoretical attention to the “power-seeking interests of the units” along with the “relative sizes of the Great Powers” in explaining foreign policy choices (1998, 26).

Many agree that Schweller is one of the scholars who demonstrated the analytical utility of neoclassical realism (Rose 1998) by emphasizing the interaction between unit-level and systemic-level variables. In an effort to make structural realism available as a theory of foreign policy, not just international politics, Schweller widens the range of state interest by taking a close look at political goals shaped at the domestic level (1998, 22). His revision of structural realism is a significant contribution to IR scholarship aiming at theoretically informed explanations of historical phenomena. But Schweller’s model is built around the notion of polarity while leaving the determinants of political goals unclear. As Rose (1998, 164-165) points out, Schweller failed to conceptualize the “sources of revisionism” that drove Nazi Germany, Soviet Russia, Fascist Italy, and Imperial Japan towards aggressive foreign policy. The reason is, I suspect, because his unit-level factors remained complementary to the systemic master variable, polarity. The realist preoccupation with polarity has much to do with the paradigm’s close association with security studies, particularly those paying little or only a passing interest in the links between security and the domestic political economy.¹⁰ Redressing this limitation requires us to turn to an alternative framework in which polarity, not alone but alongside domestic social orders, shapes international outcomes.

Why did the balance of power not work during the interwar years in a way to stem the tide of fascist aggression? Or more specifically why did it take so long to function properly? To answer this question, it is necessary to reconceptualize the nature of world politics, particularly great power rivalry. True enough, great powers have competed over power throughout history and very likely will continue to do so. Yet the advent of the modern world led great powers to take seriously the balance of social orders, not just the balance of power. David Skidmore defines social order as “the arrangement or distribution of power and interests among relevant organized groups within society” (1997, 4). It denotes a “larger system of social power” in which a political regime, an economic system, and a dominant ideology are organically interconnected (1997, 4). Any social order as a way to govern power relationships begets winner and losers, and it is consolidated through managing competition over scarce resources among classes, sectors, and other forms of organized interests. When a social order fails to govern power struggles among its contending groups, it is subject to challenges from within, as well as from without. Skidmore points to the transnational nature of social orders. Different states may share a social order’s essential elements, so “basic patterns of social organization are isomorphic across societies and where networks of interests are organized transnationally” (1997, 4). Although the compatibility of regime type or ideology had been part of the equation even in the premodern world, social orders have become increasingly transnational “with the steadily growing integration of the capitalist world economy” (1997, 4).

Skidmore acknowledges the time-honored tradition of taking seriously the social foundations of international politics. His list of scholars (1997, 13-14) who paid attention to “contested social orders” includes Polanyi and Ruggie. Of particular importance is the intellectual contribution of Polanyi who viewed the collapse of the nineteenth-century balance-of-power system as related to the crumbling of international economic order. The Hungarian émigré’s historical- sociological acumen laid the foundation for our understanding of the links between the domestic and the international political economy. But Polanyi’s ideas need to be elaborated so that they can be fully utilized within the analytical boundary of IR scholarship.

Arguably Polanyi’s most important contribution to the study of world politics would be his insight into the connections between the international order and the workings of global capitalism. Polanyi attributes the long peace of the nineteenth century to the intertwined relationship among the balance-of-power system, the international gold standard, the self-regulating market, and the liberal state. And yet the four components are not of equal importance but rather constitute hierarchical relations. “The gold standard was merely an attempt to extend the domestic market system to the international field; the balance- of-power system was a superstructure erected upon and, partly worked through the gold standard; the liberal state was itself a creation of the self-regulating market. The key to the institutional system of the nineteenth century lay in the laws governing market economy” (Polanyi [1944] 1957, 3). Polanyi’s view of the nineteenth-century international order is a mixture of the second- and the third-image explanations. However, he prioritizes the self-regulating market as a national-level factor that shapes the other three factors in varying degrees. Polanyi was a precursor in exploring the domestic (economic) sources of international (political) outcomes.

Despite the insights he provides in The Great Transformation, Polanyi’s characterization of the pre-World War I international order is problematic on three counts. First, it fails to recognize the pure political nature of the balance-of-power system. Second, his view of the liberal state as “a creation of the self-regulating market economy” is also problematic but can be maintained as to the cases of Britain and the United States in some respects. Polanyi’s second-image account of a foregone era is related to his preoccupation with the “British model” (Blackbourn and Eley 1984, chap. 3). Third and relatedly, the liberal state was far from a standard regime type for most European and Japanese ruling elites and their social allies. Despite the growing heterogeneity in regime type, the common denominator in domestic politics was illiberalism and the retarded or arrested progress of democracy. Even in Britain and the United States, transition to democracy during the second half of the nineteenth century was nowhere near complete (Rueschemeyer, Stephens, and Stephens 1992, 95-96, 122). More to the point, the nineteenth century was largely peaceful and prosperous particularly in the belle époque in no small part due to the similarity of social purposes deemed crucial to major industrial nations: no drastic changes to oligarchical rule, democratic and autocratic alike, coupled with capitalist civilization were tolerated.

As Eric Helleiner (2019, 1115) rightly notes, “Polanyi had more ambitious socialist goals in mind than welfare states and Keynesian-style macroeconomic management” for a postwar world, and for that reason his notion of embeddedness is much wider than that employed in Ruggie (1982). But such a wider notion also causes the fuzziness of Polanyi’s use of the term. The lack of specification in The Great Transformation allowed Ruggie to coin the term, embedded liberalism, and use it to denote the post-World War II international economic order. Polanyi’s main argument is that the idea of self-regulating market was invented at a certain point in time and place. The market as an institutional arrangement for economic activities had existed, from the perspective of Polanyian economic anthropology, long before the advent of industrial capitalism. It had a wider range of historical configurations than classical liberalism would have us believe (Polanyi [1944] 1957, chap. 5). For Polanyi, the self-regulating market reflected the constellation of social forces in Victorian England. It was an historical construct. With a more specific goal, complementing hegemonic stability theory, in mind, Ruggie successfully borrowed Polanyi’s idea to make distinct the content of the international regime for trade and finance that emerged after 1945.

In specifying the notion of embeddedness, however, Ruggie (1982) suggested an innovative way to understand the defining features of the interwar years by distinguishing power and social purpose as sources of political authority. His seminal work was part of the larger project on international regimes, and it was focused on the issue areas of trade and money. But there is no good reason to limit the use of his ideas to the subfield of IPE. When Ruggie’s notion of social purpose is employed in a more systemic way, we can ask the following questions regarding the interwar period. First, why have social orders become so contested after World War I? Second, how can social order be distinguished from regime type? Based on answers to those questions, we can proceed to argue, for example, that the Cold War―not a cold war¹¹―was the contestation over social order as well as power. States compete and even go to war over social order; they also cooperate to maintain a social order they have in common. It is important to note once again that social order here refers to a modern phenomenon. The emergence of nation-states and the geographical expansion of industrial capitalism added to the variety of social orders. The interwar crisis is closely associated with great power rivalry over political-economic models constructed to cope with the “internationally structured (uneven and combined) spread of capitalist relations” (Anievas 2014, 216).

Also related to the contested social orders approach is a group of scholars committed to Marxist IPE. For example, Sandra Halperin (1997; 2004, chaps. 6 and 7) offers an intriguing class-based account of the twenty years’ crisis by focusing on the reluctance of British and French policymakers to ally with the Soviet Union against Nazi Germany.¹² Unlike the traditional and popularized focus on British appeasement towards Hitler’s territorial expansionism, Halperin attributes the diplomatic folly to the anti-Bolshevism prevalent in interwar Europe (2004, 221-222). Allied military intervention in the Russian civil war soon after the Bolshevik seizure of power clearly signified that international relations were inseparable from the domestic political economy. Britain’s military action in the wake of November 7, 1917 slowly but clearly revealed the intention of capitalist great powers. Britain sent troops to Murmansk in late July 1918 with an ostensible purpose of defeating German forces, but “their underlying purpose … was to attack the soldiers of the revolution in Petrograd” (Haslam 2021, 17). Now in power, Lenin made clear that “the supreme aim of his state was revolution in all European countries, preferably by violence” (Westad 2017, 28; italics in original). In anticipation of Russian communism’s expansion, capitalist great powers, the United States and Japan included, engaged in military operations against the Bolsheviks. The Cold War had its interwar origins as a hot war.¹³

But social orders during the interwar years became both more divergent—beyond a head-on confrontation between capitalism and socialism—and more important in shaping great powers’ international behavior. Surely, the Great Depression was a crucial dividing line between an old order and a new one, at least domestically. They became more diverse because there emerged three, not two, competing alternatives to laissez-faire capitalist oligarchy of the nineteenth century. Liberal states, if they were to avoid social disintegration, had to accommodate working-class demands mostly with the use of economic heterodoxy (Gourevitch 1986, chap. 4), while assuring enlarged participation in parliamentary institutions. Illiberal states had two options, fascism and communism, and the paths taken reflected the level of capitalist development and the strength of the political center, or what Gregory Luebbert (1991, 234) called “Lib-Labism.” Either way, autocracy was firmly established. Fascism and communism parted ways on governing the economy; the former maintained capitalism but with a heavy dose of state control, while the latter wiped out capitalist relations of production. Previous phases of world politics show the heterogeneity of social orders, too, but it meant not so much as it did after World War I. As countries and regions around the 1900s became more interconnected, the divergence of social orders and domestic regime types began to affect decisions and nondecisions of major powers. The crux of the interwar crisis, in retrospect, was that liberal states more hated communism and less feared fascism. The United States did not perceive Mussolini’s 1922 March on Rome as a major threat; rather, American elites and policymakers were supportive to Italian Fascism. Richard Washburn Child, the then U.S. Ambassador to Italy, gave Mussolini every assurance that Washington “would not object to a Fascist-led coalition government” (Ben-Ghiat 2020, 24). In 1926, the U.S. government even provided Mussolini with a \$100 million loan through the brokerage of Thomas Lamont, a J. P. Morgan banker (Ben-Ghiat 2020, 27). Mussolini received favorable media coverage in major newspapers including the New York Times; the Italian socialist-turned-fascist was portrayed as a determined leader who was putting an end to the biennio rosso. Return to normalcy was the zeitgeist of the capitalist world during the 1920s (Diggins 1972, 24-25, 30). Appeasement, from the perspective of contested social orders, was not just an aberration from the traditional balance of power but, more crucially, an indication that transnational class politics finally came to the fore.

The balance of social orders took on an added importance to great powers in the aftermath of World War I because the conflict ended an old order, while facilitating the search for a new one. The balance of power remained still the major source of state choices during the interwar period, but it was conditioned by the underlying constellation of social purposes among the great powers of Europe (including the Soviet Union), Japan, and the United States. It has become a commonplace to start with the League of Nations and its idealist architects to get a sense of what went wrong during the interwar years. But the convention, both academic and popular, provides nothing but a superficial characterization of international relations during the 1920s and 1930s. The real issue for major member states of the League was still to manage the balance of power, a social construct bequeathed from the long nineteenth century. The core of great power diplomacy from 1919 through the early 1920s was no doubt the “German problem” on which the two European stakeholders, Britain and France, had almost irreconcilable standpoints. A. J. P. Taylor (1963, 64-65) gives a concise summary of the difference: “The French wanted the League to develop into a system of security directed against Germany; the British regarded it as a system of conciliation which would include Germany.” At the same time, it was a different kind of balance of power in the context of socialism’s rising tide. Heightened class and sectoral tensions in major industrial countries rendered the calculus of world politics significantly shaped by the arrangement of “social forces” (Cox 1986) in the national context. Major European powers, the United States, and Japan diverged in their choice of the way to restore domestic stability and secure a better position in international rivalry. Divergence of social purposes was moderate among some countries but sharp among others, making a legitimate international order unlikely.

In this section I offer a typology of international order, combining the realist argument on polarity with varied scholarship on the social dimensions of interstate relations. This typology helps us to get a better understanding of the twenty years’ crisis in relation to other time periods of world politics. The realist dimension of Figure 2 is taken from a widely used variable of polarity that is operationalized as the number of poles (or great powers) within the international system. The other dimension represents the balance of social orders that varies from congruent to incongruent. While the measurement of polarity can be done in a fashion widely accepted within the field of IR, determining the degree of congruence and incongruence is tricky at best. The notion of social orders is a composite one that includes characteristics of political regimes, economic systems, arrangements of social forces, and ideational trends. Alexander Wendt (1992) has provided us with an essential conceptual tool for understanding balance of power as a social construct. While retaining his constructivist spirit, here I look more closely into how an international order is linked to constellations of national political economies in terms of interests rather than ideas. This is an analytical choice in accordance with the spirit of critical realism.

Figure 2 shows six mixes of varying values on two dimensions of great power politics: polarity and congruence/incongruence of social orders. The unipolar- congruent mix represents an international order in which cooperation among major states is maintained under the aegis of a predominant state. The unipolar-incongruent mix represents an international order in which cooperation is usually the norm but a note of discord surfaces among major states every so often. The bipolar-congruent mix represents an international order in which two great powers confront each other with backing from each bloc or sphere of influence. The bipolar-incongruent mix represents an international order where two great powers exist but neither enjoys enough and reliable backing from its allies. The multipolar-congruent mix represents an international order in which more than three great powers usually cooperate because they are like-minded states. The multipolar-incongruent mix represents an unraveling of the international order because more than three states with mostly incompatible worldviews compete over primacy.

Measuring polarity in terms of the number of poles within the system seems self-evident, but it is not that simple. Schweller’s distinction between tripolarity and multipolarity derives from the difference between polarity as the structure of an international system and polarization as the pattern of state behavior. The analytical weight placed on the latter allows Schweller to complement realist balance-of-power theory by taking into account unit-level factors such as interests and identities, although his work fell short of being fully neoclassical as I argued earlier. While following the conventional wisdom that tripolarity is most prone to war, I see no need to give it the status of a distinct category of polarity. Schweller did so because his main goal was to explain the causes of World War II, while mine is to understand the role of competing social orders in shaping great power rivalry in a certain direction during the interwar period.

Differences in domestic political economies may be fleshed out by drawing on Mansur Olson (1982)’s notion of “social rigidity.” Olson argues that national variations on economic growth can be attributed to the level of social rigidity which is related to the duration of political democracy and the strength of “distributional coalitions.” Stability over an extended period without disruption by war, foreign occupation, or revolution leads to social rigidity, which in turn reduces the urgent need to adapt to external changes. Olson notes, however, the importance of “encompassing organizations” in making possible economic growth under stable democracy. The best example is small states such as Sweden and Norway where encompassing associations of both organized labor and organized capital are strong due to their late industrialization and social homogeneity. Britain experienced the worst case of stagflation during the 1970s because its high level of social rigidity, an outcome of the oldest democracy with no disruptions from the outside, was exacerbated through the weak development of encompassing associations. France falls on the same category as Britain, but its postwar economic growth was fast because a long duration of political instability and the German occupation during World War II weakened distributional coalitions themselves. Rapid economic resurgence of West Germany and Japan after 1945 was a combined outcome of low social rigidity and well-developed encompassing associations. Olson also suggests that the cases of West Germany and Japan reflect their experience of highly authoritarian, almost totalitarian in Nazi Germany, regimes before 1945.

Olson’s argument can be reasonably applied to explaining varying responses to the twenty years’ crisis. Nazi Germany, Imperial Japan, and Soviet Russia could respond to the changing environment of international security and the world economy with illiberal policy packages because social rigidities were low through war and revolution and distributional coalitions were crushed by state violence. Britain and France for much of the interwar period are the best examples of the failure of conservatism to make adjustments to external changes. Elites in both countries were deeply tied to the imagined restoration of the belle époque, which impeded their ability to mobilize the masses and resources in preparation for war and in response to economic downturns. The U.S. reluctance to assume the mantle of leadership after World War I reflected the inward-looking nature of pre-New Deal distributional coalitions rather than American elites’ zeal for restoring the nineteenth-century liberal order. The lack of a feudal past, no disruption from direct security threat due to its location, and its vast size, however, produced mixed results in policy changes at both the domestic and international levels (Olson 1982, 92-94). After the shock of the Great Depression, the U.S. government rapidly moved on to making changes to its domestic and international policy packages with the backing of an internationalist distributional coalition (Ferguson 1984).

Social purpose is closely related to the nature of a domestic political regime but cannot be either reduced to or identified with the latter. States with different political regimes can share a similar social purpose, for example, the free trading system during the last third of the nineteenth century. The pre-1914 Europe (and East Asia) was characterized by an unstable balance of power as a result of trade expansion (Rowe 1999), while the great powers during the interwar period had a clearly defined, if not stable, balance of power in view as a consequence of the war and were less subject to the vagaries of international economics than in the belle époque. The systemic distribution of power resources or capabilities during much of the interwar years was unmistakable. Nonetheless, liberal states failed to balance against Nazi Germany because their state and ruling elites were not in unison on the relative importance of balance of social orders (Halperin 1997, 150-152). Both Britain and France during the latter half of the 1930s showed great confusion about what to do in managing the two illiberal challengers, Nazi Germany and the Soviet Union, along with lesser illiberal powers such as Italy and Japan. The focal point for capitalist democracies since 1917 had become the threat of communism because they had long been confronting socialist agitation and working-class demands at home. Hitlerite Germany was becoming disruptive to the European balance of power, while the fear of international communism had taken root in the minds of European ruling elites and their American and Japanese counterparts since the days of Lenin. Just a few years before another great war, the mindset of “Better Hitler than Stalin” was widely observed (Taylor 1963, 146).

Agreement can be easily reached that the interwar period best exemplifies the multipolar-incongruent mix of Figure 2. But this seemingly facile categorizing needs some modification via temporal specification. From the perspective of contested social orders, the interwar period can be subdivided into the 1920s and the 1930s, although this distinction is somewhat rough. The Great Depression is the most crucial dividing line because incongruence in social orders became acute as great powers coped with the economic crisis in qualitatively different ways. During the 1920s one can observe democratic regimes sticking to varying degrees of economic orthodoxy as represented in Britain and the United States before Franklin Delano Roosevelt came to the White House. Still reeling from the Great War, France lacked a political coalition to deal with reconstruction and industrial rationalization along with a reexamination of military doctrine (Joll 1990, 292-293). Liberal states would not have extricated themselves from the relics from the nineteenth century until the Crash of 1929. Particularly, the French insistence on German reparations and the war debts incurred by both Britain and France to the United States formed a vicious circle, which fueled fascism in Germany. Retrospectively futile efforts to revive the defunct nineteenth-century liberal order were followed by a variety of illiberal political-economic experiments during the 1930s. Policy innovation in liberal states further eroded the foundation of global capitalism. The United States after 1936 and France in 1936-1937 used heterodox economic policies within the political framework of pluralist democracy. And small European countries managed to establish social democratic regimes. Dictatorial regimes pursuing varying degrees of economic heterodoxy were observed in Nazi Germany, Fascist Italy, Imperial Japan, and Soviet Russia (Gourevitch 1984, 102, table 1; Luebbert 1991). A mix of autocracy with varying degrees of economic orthodoxy is logically and empirically improbable for the interwar years, although some country cases in other time periods—e.g., Chile under Pinochet—may be put into this category.

The long peace of the nineteenth century under the Concert of Europe may be reasonably assigned to the multipolar-congruent mix, although the role of British hegemony varied throughout the period. This period is also well known as the heyday of diplomacy under the European system. Classical realism, best exemplified in the works of Hans Morgenthau (1973, 216-217) and Henry Kissinger (1964), pinpoints the importance of diplomacy in maintaining such a delicate equilibrium among great powers, none of which could claim primacy. The multipolar-congruent mix, however, can also be observed in what Jens Steffek (2015) calls “fascist internationalism” along with emerging forms of cooperation among illiberal states. Steffek (2015, 5) argues that fascism is not a monolithic ideology but an amalgam of distinct visions of economic and social organization by looking into Italian fascist intellectuals of a modernist outlook. Fascist or other illiberal states could have committed themselves to international cooperation, but illiberal internationalism is very likely to be confined to technical issues. Furthermore, illiberalism’s technocratic vision and its liberal equivalent can be rarely on the same page because the latter is not free from democratic accountability. Arguably this possibility, i.e. a world co-managed by more than three great powers sharing illiberal values, is the last thing a liberal hegemon such as the United States would want to see especially when its power and prestige are in decline. Generally speaking, when the multipolar-congruent mix is based on a superficial likeness, unlike what Robert Keohane (1984) hoped for, an extended liberal international order “after hegemony,” such an international order is susceptible to challenge from a rising power or group of revisionist states.

One may be quick to identify the post-World War II liberal international order as the bipolar-congruent mix. Considering that the Cold War had the effect of reducing the difference in social purpose among major industrial nations, however, it would be more accurate to characterize the post-1945 embedded liberal order as having aspects of both the bipolar-congruent and the multipolar-congruent mixes. The relationship between the United States and advanced industrial states especially since the early 1970s was a tensioned one (Webb 1995; Helleiner 2019, 1114). All in all, U.S. predominance in military and economic power provided the international system with stability, and the hegemon’s “soft power” (Nye 1990) glued the democratic capitalist states together. In the U.S.-led Western bloc, it was tantamount to cooperation among like-minded states. In the Soviet bloc, however, it was more an empire than a set of normal relationships between sovereign states.

The bipolar-incongruent mix was observed during various phases of the Cold War, particularly since the 1960s. In the U.S.-led capitalist bloc, cooperation on the side of many developing countries was more a systemic imperative than a calculated choice. Developing countries with varying combinations of authoritarian politics and dirigiste economic governance had to figure out how to deal with the United States and other advanced industrial states in securing economic support and military protection (Krasner 1985). In the Soviet bloc, this type of relationship was observed during the later phase of the Cold War.

The unipolar-incongruent mix also implies an unstable order of “liberal pessimism” in which rapidly growing states find themselves “potentially dissatisfied with the political status quo” (Haggard 2014, 2). One might say that the present crisis of the U.S.-led liberal international order is an empirical referent of this mix. But in order to say so one should be able to observe viable alternatives to the still towering model of liberal capitalist democracy. How to assess the stability of this mix largely depends on what we mean when we say there is a pole. Most structural realists would not hesitate to recognize a state as a single pole when the distribution of material power is definitively skewed toward it. Although this article suggests a critical realist view of international order, I take the standard structural realist measure of polarity as a bottom line. Yet at the same time principles, norms, ideas, and ideology matter in determining who rules the world. Power alone does not guarantee the stability of an international order. It would be safe to say that as yet we have not seen an international order exactly befitting this mix.

This article has tried to figure out what constitutes the twenty years’ crisis in an eclectic fashion that retains the kernel of the realist argument and complements it with critical insight gleaned from an extensive and diverse body of literature on social dimensions of world politics. My argument has proceeded in the following order. First, I looked at Carr’s view on the crisis and found out that his account of the transformation of world politics during the interwar period advanced a genuinely novel perspective that I call here critical realism following the usage by some previous authors (Falk 1997). Second, I reviewed central tenets of structural realism and neoclassical realism as to the interwar period and reconfirmed that the realist preoccupation with the balance of power fails to capture the social foundation of the interwar crisis. Third, I endorsed the contested social orders approach as a corrective to the mainstream realist logic by examining how the approach is employed both conceptually and historically in accounting for the interwar crisis. Fourth, I offered a typology of international order by combining the structural dimension of polarity and the unit-level dimension of social order compatibility, utilizing the prior research on the effect of domestic political economies on states’ international behavior.

My typology may be applied to a wider range of historical and contemporary cases. As a way to increase the external validity of my argument here, it is necessary to test the critical realist model against more time periods other than the interwar years. Because my typology’s main function here is to clarify the distinctiveness of the interwar crisis, discussions on each type are sketchy at best. Indeed, each type may include a number of historical and/or contemporary cases. For example, the stability of the Concert of Europe as an international order based on cooperation among like-minded states needs to be carefully examined in comparison with the cases of illiberal peace which may be observed more frequently as China and Russia grew rapidly into revisionist challengers to the now crumbling post-1945 liberal order.

This kind of comparative-historical analysis will be helpful in clarifying a causal relationship between one time period and another, either preceding or succeeding. The tragedy of the interwar years lies in its connection with the long peace of the nineteenth-century liberal order that failed to accommodate emergent social purposes within its remit. The current turbulence of world politics after 2016 cannot be reduced to all the eccentricities of Donald Trump as a maverick politician (Cha and Seo 2018). Similarities surely exist between the two time periods in terms of a demagogic rise, and yet they need to be systematically understood from a viewpoint suggested in this article. Just as the Nazi seizure of power through electoral success and the use of political violence encouraged other dictatorial regimes to take bolder (and disastrous, retrospectively) moves during the rest of the decade, so did Trump’s election victory and encouragement of partisan violence during his presidency fan the flame of right-wing populism and neo-authoritarianism with nationally distinct guises around the globe. The Nazi vote share reached its peak at 43.9 percent in the March 1933 Reichstag election, yet as Richard F. Hamilton (1982, 3-4) emphasizes, the most critical moment in Hitler’s path to power was the July 1932 election in which the NSDAP garnered only 37.3 percent of the vote. The German conservatives, who never abandoned their nineteenth-century hubris, accepted Hitler’s appointment as Reichskanzler on January 30, 1933. In the 2016 presidential election Trump lost the popular vote to Hillary Clinton by 2.1 percent and yet won the race only due to the absurdity of an electoral college system. Republican leaders and their wealthy donors, who have hardly been eager to deal with the central issues of post-Cold War global capitalism, made the most of the Trumpian rule of the game, exacerbating political polarization to just win.¹⁴

Despite those similarities, many important differences between Nazi Germany as a dissatisfied great power and Trump’s America as a “weary titan” (Friedberg 1988) should be reminded as a precaution against hasty historical analogies. As Jonathan Haslam (2021, viii) put it, “The indifferent application of our understanding of interstate relations in one epoch to an entirely different time is not a sound recipe for success.” The interwar crisis reflected a multipolar (or tripolar à la Schweller) distribution of power combined with stark differences in the ways nationally devised collectivist political economies projected themselves onto the world. The wrecking of the American-led postwar liberal order should be viewed in a larger post-Cold War context in which unipolar complacency eliminated “exit options” for participants in the neoliberal regime, laying the foundations for populist backlash (Cooley and Nexon 2020, 7-8). The rise and fall of an international order has its own sources and causes, which often defy robust comparisons, let alone an easy categorization. But at the same time accounting for an international order or a lack thereof requires a keen eye for a concatenation of factors that often translate into a comparable pattern. In this regard, it would be reasonable to locate the links between the seemingly stable and rosy phase of globalization in the 1990s and the current crisis of the U.S.-led liberal international order with the aid of historically grounded macro-comparisons.

Making sense of the twenty years’ crisis is a worthwhile cause not only in terms of knowing the past but also in terms of avoiding the same mistake in our lives. A pervasive sense of the post-1945 liberal international order’s untimely erosion may drive an alarmist argument based on an historical analogy with past experiences such as the policy of appeasement in the late 1930s (widely believed to be a failure) or the strategy of containment in the late 1940s and early 1950s (not universally interpreted as a success): a revisionist state or coalition is on the horizon and must be stopped. Fascism was a serious alternative to the crumbling liberal order during the interwar period, and communism posed a transnational threat to capitalist civilization from 1917 to 1991. Does the world now know a transnational, social order supporting geostrategic ambitions of a revisionist state or coalition? Answering this question properly requires a judicious use of critical realism that observes both power and purpose in world politics.