Correspondence: Paradigms and Power

John Mearsheimer routinely argues that only realists are capable of “thinking deeply about power politics, ” but most of his audience remains unpersuaded. In this article, he blames the continuing influence of approaches that “either ignore or misconstrue” key military variables and thus blind people to the true implications of the shadow of war for great power politics (p. 7). 1Much about this article feels dated. The paradigm wars are long over. Russia launched its full-scale invasion of Ukraine four years ago. European powers are expanding their defense capabilities. Experts weigh the military balance in Asia—and the possibility of a Chinese invasion of Taiwan. The Donald Trump administration rejects liberal internationalism; it is systematically degrading—and sometimes outright destroying—myriad nonmilitary instruments that once played a key role in the U. S. approach to great power competition. Meanwhile, theoretical pragmatism and methodological pluralism are rejuvenating the study of power politics. The key wagers of a post-paradigmatic research program have already started to emerge: (1) the overwhelming majority of power-political competition, even when military instruments are in play, does not involve the direct use of force; (2) researchers should analyze the full range of capabilities that actors use to jockey for influence-including information, wealth and economic flows, social and diplomatic networks, institutional prerogatives, and non-kinetic uses of military capabilities; (3) analysts should not treat military instruments as inherently different from nonmilitary ones. Instead, they should focus on how, why, and under what conditions actors try to use diverse capabilities to achieve similar goals. For example, actors can and do attempt to “wedge” apart rival coalitions—whether in the form of interstate alliances or domestic political consensus—through threats of force, economic levers, propaganda, and any number of other resources. The same is true of efforts to “bind” existing or potential partners, whether in the context of military defense pacts or transnational ideological networks. 2The reduction of “realism” (p. 23) to (often crude) claims about the overriding importance of “military variables” (p. 17) dates from the early phases of the paradigm wars. It does not follow that “war casts a giant shadow over international politics” (p. 11). Mearsheimer himself admits that great power war is “unlikely” (p. 17), and that war between the current major powers is “especially unlikely” (p. 18) 3 He tries his best, but he cannot write his way out of the obvious implication: The effects of the “shadow” of war are contingent and underdetermined. This is about more than abstract theory. The road to great power escalation runs through both military and nonmilitary instruments. Vladimir Putin annexed Crimea and intervened in Ukraine in 2014 after years of power-political competition with the United States and the European Union—which had been carried out almost entirely through economic assistance, trade negotiations, information operations, and non-kinetic capabilities. China uses military instruments to control Taiwan, but it also makes heavy use of propaganda, economic carrots and sticks, and many other power-political instruments. It is necessary to understand not only the dynamics of such instruments, but also how they interact with one another. 4Indeed, if policymakers and scholars take Mearsheimer's advice and obsess about an improbable great power war, they risk overlooking the wide range of economic and diplomatic instruments that might help prevent this very outcome. The combination of multipolarity and Mearsheimer's military myopia might make great power war appear inevitable. —Stacie E. GoddardWellesley, Massachusetts—Paul K. MacDonaldWellesley, Massachusetts—Daniel H. NexonWashington, DCThere is much to agree with in John Mearsheimer's essay about the relationship between war and great power politics. 1 But there is a glaring problem with his characterization of the current international system as multipolar. Mearsheimer states that the international system was unipolar from 1991 until “about 2017, ” when “China and Russia had developed sufficient economic and military capabilities to qualify as great powers, thus making the world multipolar” (p. 7n1). Polarity has important consequences for international stability, as Mearsheimer and other realists note. 2 This claim makes determining the polarity of the international system important. There is little doubt about China: Its growth clearly makes it a great power. 3 But is Russia a peer to the United States and China? To back up his claim, Mearsheimer provides only a statement by the first Donald Trump administration (p. 7n1). This evidence does not suffice. If the world had shifted from unipolarity to multipolarity around 2017, then there must be evidence that Russia has grown sufficiently to become a peer to the United States and China. There is none. Russia's gross domestic product was just 1. 61 trillion in 2024, compared with 18. 49 trillion for China and 22. 57 trillion for the United States. 4 Russia's economy was only 11. 25 percent the size of the U. S. economy in 1991, and in 2024 it was even smaller, at 7. 09 percent. 5This decline in relative wealth is accompanied by a decline in Russia's conventional military power. For example, China and the United States both have at least two types of fifth-generation fighter planes, but Russia has been unable to develop its own. On the seas, Russia has not had an operational aircraft carrier since 2017, whereas China's third aircraft carrier is about to become operational. 6 On the ground, Russia's difficulties in overcoming Ukraine in conventional war only underline its general military decline. Russia does possess several thousand nuclear warheads that it can deliver at long ranges, but it has had that capability for the entire post-Cold War period. Having these nuclear warheads in “about 2017” does not represent a change in Russia's capability or a shift in its power status. If nuclear weapons did not make Russia a great power in the 1991–2017 period—which Mearsheimer characterizes as unipolar—they cannot be the basis for changing Russia's status after 2017. Unipolarity may be over, but it is likely being replaced by a U. S. -China bipolarity, not a U. S. -China-Russia multipolarity. —Rajesh RajagopalanNew Delhi, IndiaI appreciate the opportunity to respond to the critiques of my article, “War and International Politics. ”Let me first respond to the comments of Stacie Goddard, Paul MacDonald, and Daniel Nexon. First, they say I argue that “only realists are capable of ‘thinking deeply about power politics’” (p. 7). This is a mischaracterization of my argument. My point was simply that policymakers and students of international politics did not pay much attention to great power politics during the unipolar moment because these issues were taken off the table, given there was only one great power in the world. Second, Goddard et al. claim that “the paradigm wars are long over” and the international relations (IR) field has moved on to “a post-paradigmatic research program. ” I disagree. Paradigms are bodies of theories, which are widely considered essential to understanding how international politics works. Liberalism and realism, for example, have long dominated the academic and policy discourse because they provide the best, though by no means perfect, tools for making sense of the world. Although new theoretical approaches regularly appear, none have rivaled liberalism or realism in longevity or explanatory power. Until they do, the traditional paradigms, to include liberalism and realism but also constructivism, Marxism, and critical theory, will continue to offer the most compelling accounts of great power politics. Moreover, even if a new body of theory emerges, IR will, by definition, remain a paradigm-centered research program. Third, contrary to what Goddard et al. say, great power war need not “appear” likely, let alone “inevitable, ” in order to cast a giant shadow over international politics. Given the horrendous consequences that usually attend great power wars, the likelihood of becoming involved in one does not have to be high to cause policymakers to pay a great deal of attention to that possibility. This is especially true when the great powers have nuclear weapons. I do not think a war between the United States and either China or Russia is likely, but it is certainly an ever-present possibility and therefore a cause for enormous concern. Fourth, Goddard et al. criticize me for overemphasizing the importance of military variables and “overlooking the wide range of economic and diplomatic instruments” that also contribute to conflict. I do not deny that there are several military and nonmilitary causes of war, but my article was not about the causes of war. Rather, it addressed how the possibility of war shapes the behavior of states and the basic character of world politics. Rajesh Rajagopalan contests my claim that Russia became a great power around 2017. The key issue here is how one defines a great power. There is no agreement among scholars on this matter, and it is not easy to adjudicate among the competing definitions. The key criteria for assessing a definition are clarity and how useful it is for describing and explaining the world. In my lexicon, whether a state is a great power is principally a function of its relative military capability. To qualify as a great power, a state must have sufficient military assets to put up a serious fight in an all-out conventional war against the most powerful country in the world. It need not have the capability to defeat the leading state, but it must have some reasonable prospect of turning the conflict into a war of attrition that leaves the dominant state seriously weakened. In the nuclear age, a great power must also possess a survivable nuclear deterrent. On Russia's reemergence as a great power, a 2019 RAND report noted that it had “the ability to fight a major ground war with the West or China. ” Moreover, not only did it have “extensive conventional and nuclear … capabilities, ” but “its current and projected near-term capabilities pose a threat to the U. S. Army in Europe. ”1 Given that description of Russia's military capabilities, which is backed up by other sources, it qualifies as a great power by my definition of that term. —John J. MearsheimerChicago, Illinois