John Mearsheimer is renowned among those in government, think tanks, and universities who reflect on strategy and foreign affairs. Despite that, he is something of an outlier. It is not merely that he is a realist where most are idealists, but that the account of rationality he relies on in his work is at odds with the majority theory. The R. Wendell Harrison Distinguished Service Professor of Political Science at the University of Chicago, and with books published by the most prestigious presses in the land, Mearsheimer has risen as far as anyone can in the world of ideas. Yet ever since the Clinton administration’s turn to idealism in foreign affairs, the world’s best-known realist thinker has been a voice crying out in the wilderness. Like his namesake, John the Baptist, much he foretold has come to pass, not least in Ukraine and Israel.

How States Think: The Rationality of Foreign Policy, co-written with Sebastian Rosato at the University of Notre Dame, challenges the twin pillars of the contemporary inquiry into international relations. The book reveals a weird disconnect between the rational choice theory and political psychology of thinkers in the foreign policy establishment, and the ground-level thinking of political and military planners. It explains a good deal.

“Expected utility maximization, a concept at the heart of the rational choice enterprise, is widely considered the canonical definition of strategic rationality.” Along for the ride, and a growing sub-discipline in the academy, political psychology contends that most individuals and states act irrationally. “Political psychologists define nonrationality as deviation from expected utility maximization, which they call bias.”

Mearsheimer and Rosato complain that these theories are narrow and incomplete and, more to the point, they mangle policy. Firmly entrenched amongst the foreign policy literati, these theories explain why “it has become commonplace for American leaders to describe their foreign adversaries as nonrational.” The volume opens by documenting a damaging trope. Quoting senior politicians and policy documents, we learn that Putin—and you can plug in the name of any other recent adversary of the US—is an “ego-driven” obsessive, a “power-hungry megalomaniac,” and an “unbalanced autocrat.” Joe Biden sums up the Russo-Ukraine War: “It’s irrational.” Reading the book, a bewildering thought stirs: the enormous US establishment of government, think-tank, and university thinking about foreign affairs is operating with a hardly believable account of rationality. So impoverished is the account that, as our authors put it, for most international relations theorists, “in essence, rationality is defined out of existence.” 

What makes this interesting book especially important is that, inadvertently, our authors show the importance of Aristotle. Aristotle is cited once, for his axiom that man is a rational animal. Our authors want to distinguish between credible and noncredible theories of strategic rationality. Part of their account relies on the professional ethics of political and military planners, but to this reader at least, their examples point away from realism towards Aristotelianism. Two of their central examples of noncredible strategic thinking vindicate Aristotle’s claim that reason does not operate adequately without the virtues. It is a conceit of realism to be hard-nosed and cynical, but the examples of Mearsheimer and Rosato show that strategic rationality is not value-free.

World War I

During lockdown, Mearsheimer and Rosato met online daily for 4-hour meetings—with only Christmas Day excluded. The book thus represents 3,000 hours of collaborative endeavour over Zoom. Later, with restrictions lifted and a draft in hand, there were private gatherings with colleagues to debate the coherence of the ideas. The structure and writing are exemplary. Anyone interested in world affairs will easily lap up the opening theory section on rationality and enjoy the latter part devoted to the historical record of political and military planning. It’s the perfect book for those who like both philosophy and history! 

Mearsheimer and Rosato do not subscribe to the majority’s position on rationality in world politics. “It is a good way to decide how to achieve one’s objectives in an information-rich world where reliable data is abundant, but international politics is information-deficient and uncertain.” If “expected utility maximization”—the idea that we choose amongst a ranked order of probable outcomes that action most likely to deliver our interest—is knee-capped by lack of data, how have strategists and planners coped in the past? Thankfully, they relied on political theory and a knowledge of history.

The record shows, contend Mearsheimer and Rosato, that political and military planners are mostly examples of homo theoreticus, i.e., persons who employ a credible theory about the way the world works and participate in a deliberative process. A credible theory has coordinates: it takes survival of the state as basic and assumes uncertainty about the context for action. In opaque conditions, planners must lean on theory. “When the stakes are high, however, as in matters of national security, they have powerful incentives to think in theoretical terms.” Testimonies show that planners pick a theory that “best captures the way the world works.”

Mearsheimer and Rosato relay that WWI is a baseline for much thinking in international relations; the Great War “looms large in many theories of war and peace.” Against many WWI history books, which tell us that leadership fell to “the daemonic nature of power,” “an amoral lust for battle,” and “fatuous arguments for empire,” Mearsheimer and Rosato contend that WWI is evidence that “states are routinely rational.”

For example, in a precarious geopolitical situation, with allied threats to the east and west, the German high command observed that France was growing its army, and that Russia was reorganizing after its embarrassing defeat to Japan in 1905. The Germans reasoned that it was better to strike the already well-organized French first and then turn to the Russians still in the process of a rebuild. In addition, like Napoleon, the German strategy of dominating Europe was a prelude to defeating England, the prime threat to German integrity. With their land borders secure, the Germans reasoned they would be free to take on the British navy. Germany wanted to survive, and the planning was consultative. The high command wrote memoranda which they exchanged and refined with inputs from various government departments. General Franz von Wandel, the director of the General War Department in the Ministry of War, wrote in his notes, “People are generally resolved for such a proposition.” German strategy employed a balance of power theory and developed a plan consultatively. German high command was an example of homo theoreticus. 

Noncredible Theory

Mearsheimer and Rosato document cases of strategic irrationality. This refers to instances where planners either did not think or did so relying on outlandish accounts of the way the world works. Sometimes, in addition, planners also acted high-handedly, without consultation. 

To think credibly about world politics, starting assumptions cannot be “descriptively false.” Realism and idealism are both credible, believe Mearsheimer and Rosato. Realism contends that the system of state interaction predicts how states behave whilst idealism believes that individuals’ interests to make money and live in peace generate alliances domestically and internationally. For example, since nation-states have no greater power above them to umpire their disputes, the realist expects nations to muscle up for protection. War is always a possible policy solution in realism. By contrast, idealists think humans are skilled at generating associations to manage their group affairs. In this theory, there is less security anxiety because of a high confidence that international governance, like the IMF, WTO, and WHO, can diffuse tensions. In a speech at the UN, President Clinton captured this spirit: “For our dream is of a day when the opinions and energies of every person in the world will be given full expression, in a world of thriving democracies that cooperate with each other and live in peace.” Though realists, Mearsheimer and Rosato grant: “Yet while there are good reasons to conclude that liberal hegemony was a failure, it was a rational grand strategy.”

What is not credible, however, is a theory that posits civilizational identity as basic. The reason is that political passions geal around nations far more than anything as misty as civilization. For example, the historical record shows that even during the Counter-Reformation, Catholic nations opted to balance with Protestant nations against any player in the system—Catholic or Protestant—gaining too much clout. 

Mearsheimer and Rosato argue that US policy after 9/11 was bedeviled by bad theory. Forcible democracy promotion theory is noncredible because there is no historical evidence that once a tyrant is removed a natural yearning of peoples for democracy wills out. Furthermore, Iraq policy assumed the domino effect was real, but history does not back this idea. Post WWII, though US policymakers opted for forcible democracy promotion theory many times, it has only worked in 3% of cases. The only time it is known to have worked was with the US installation of democracy in Colombia as part of the war on drugs. The domino effect is not real. For example, though the US lost in Vietnam, Communism did not run the table and sweep through Asia.

The Second Iraq War was noncredible theory compounded by a failure in consultation. Irrationality can swamp decision-makers if “silencing, coercion, suppression, lying, or withholding of information” marks an administration. According to the early historical inquiries into that time, Cheney and Rumsfeld were masters of the political “dark arts.” Concern in sectors of the administration with the cogency of the forcible democracy promotion theory was squashed, and with catastrophic consequences. There was no plan B for governance post-Saddam. General Keith Kellogg: “There was no real plan. The thought was, you didn’t need it.” It was not credible that the yearning for democracy in the diverse camps of Iraq’s peoples be expected to bear all the weight of governance.

The treatment of the Bush administration is a good example of where we find Mearsheimer and Rosato inadvertently vindicating Aristotle. Surely there is a connection between imprudent foreign policy thinking and prominent members of the Bush administration ignoring the professional ethics of political and military planning. Aristotle would predict this, since there is such a thing as virtuous reasoning. Neville Chamberlain’s near-catastrophic policy of appeasement is another example of the importance of virtue in rational deliberation. 

Aristotelian Foreign Affairs

Good political order, Aristotle proposes, depends on rightly ordering the basic drivers of our nature. His virtue theory contends that these drives require four hinge virtues. The cardinal virtues are temperance, which modifies our desire for pleasure; courage, which controls fear; prudence, which develops our reason; and justice, which directs our action on the back of the other three virtues.

Neville Chamberlain failed in prudence. Despite Hitler’s flexing, Chamberlain abandoned the longstanding British policy of balancing against any continental power rising to preeminence. Aristotle’s position is that the virtues stand and fall together. If prudence fails, then other virtues must be absent, as well. And sure enough, about Chamberlain, Mearsheimer and Rosato:

His preference for abandoning the continental commitment had no apparent theoretical foundation and instead was driven largely by emotional thinking. He was horrified at the prospect of British troops fighting another world war and wanted desperately to avoid it. In other words, he privileged fear and hope above theoretical reasoning.

Chamberlain failed in courage, but also temperance. Immodestly, he ignored the wisdom of august predecessors and the opinion of those around him schooled in war. Chamberlain did not fight in WWI but his foreign secretary, Sir Anthony Eden, MC, had fought with great distinction. Eden resigned his position in protest at the direction of the cabinet’s foreign policy. Lord Halifax, mentioned in dispatches in WWI, was a confidante of Chamberlain’s and did finally persuade him to open cabinet discussion for a course correction. Listening to other experienced hands, Chamberlain began to show greater modesty around his cabinet, the ship righted in time, and the country steeled itself for a just war.

Perhaps there were people like Eden and Halifax in the Bush administration but no course correction in Iraq policy happened. Professional ethics were absent, reason could not be made virtuous, and a profound injustice was done to the people of Iraq. 

Mearsheimer and Rosato are surely right that “expected utility maximization” will not bear good fruit in foreign affairs but core examples of noncredible strategic rationality carry them far from their own preferences and end up recommending that wise foreign policy hands rely on Aristotle and reason virtuously.