International relations theorist explains motivations of great power conflicts

The Notre Dame International Security Center (NDISC) hosted John J. Mearsheimer, the R. Wendell Distinguished Service Professor of Political Science at the University of Chicago, for a lecture entitled “War and International Politics” on January 30. 

Mearsheimer, a West Point graduate of 1970, earned his PhD in political science from Cornell University in 1981. Known for his theory of offensive realism, which holds that the desire to survive motivates state behavior in an anarchic international order, Mearsheimer has recently made headlines for suggesting that the Russian invasion of Ukraine was the result of NATO aggression. 

Mearsheimer has authored several notable books in the field of international relations, including The Israel Lobby and U.S. Foreign Policy (with Stephen M. Walt) and How States Think: The Rationality of  Foreign Policy with Notre Dame political science professor Sebastian Rosato.

Often regarded as the quintessential contemporary international relations scholar, Mearsheimer’s work has pioneered the realist perspective. In addition to being a staple of virtually every international relations course, his worldview continues to shape discourse and inform foreign policy debates in both classrooms and halls of power around the world. 

Reflecting on Mearsheimer’s influence and the success of the talk, Michael Desch, the Brian and Jeannelle Brady Family Director of the Notre Dame International Security Center, told the Rover, “It was a huge success, attracting an audience of almost 200 people in person and online. It was, in my opinion, such a hit because Mearsheimer incisively described and explained the dynamics of the world today from Ukraine, through the Middle East, to China.” 

In keeping with his realist background, Mearsheimer defined three central themes at the outset of his lecture: the essence of international politics, why states go to war, and how escalation occurs in times of war. He began his remarks by describing how the world, following the end of the  period of American hegemony, has entered a multipolar moment with the rise of China and Russia as global superpowers. 

Mearsheimer explained that war between states is an inevitable feature of international relations for two reasons: the nature and architecture of international politics. He underscored how “fundamental differences about principles” motivate political actors to “kill” one another, later characterizing power politics as a “contact sport.” Additionally, he posited that the lack of a higher authority on the world stage leads to a state of anarchy in which conflict is endemic. 

Next, Mearsheimer asserted that liberal conceptions of international relations—such as just war theory—are unrealistic in an anarchic world. He focused on the various ways that war is justified under this theory, highlighting how it considers both preventative wars and wars of opportunity to be illegitimate conflicts. He then contended that such classifications serve to “subordinate the conduct of international politics to a set of moral and legal precepts,” a proposition which Mearsheimer rejected as foolish.

Concluding his discussion of why states go to war, Mearsheimer clarified that realist thinking does not preclude states from behaving morally. Rather, he posited that when a state faces a conflict between their “moral compass” and realist considerations, they will always prioritize the realist interests.

Proceeding to his final theme, Mearsheimer examined why wars escalate, pointing to nationalism, industrialization, and nuclear weapons. He discussed how nationalism tends towards becoming “hypernationalism.” This phenomenon, he said, drives states to desire total victory and demonize the enemy as “other,” citing Napoleonic France and Nazi Germany as examples of aggressively nationalist, expansionist states. Nevertheless, Mearsheimer acknowledged that other ideologies can also push states to move beyond limited wars, suggesting that “crusader liberalism” motivated the U.S. to escalate conflicts in the Middle East and the Balkans.

In closing, Mearsheimer reiterated that “conflict is endemic to international politics,” underscoring his belief that, in the realm of international relations, realist considerations will always trump moral, economic, and legal considerations. 

In response to an audience question about the lessons that current U.S. foreign policymakers can learn from 1939–1945, Mearsheimer advocated for an unconventional approach. Similar to how the U.S. allied with the Soviet Union in World War II to fight Nazi Germany, he argued that the United States should seek an alliance with Russia to leverage itself against China. He argued that China is the main threat to American sovereignty, and thus an alliance against a lesser evil may be necessary to “balance against a greater evil.”

Sophomore Shri Thakur agreed with Mearsheimer’s sentiment, arguing for a more conciliatory tone with Russia in order to balance the Chinese threat. “Mearsheimer was totally right when he stated that America’s antagonization of Russia hurts its own efforts in deterring China, which is a more significant threat to U.S. hegemony.”

Near the end of the question and answer period, Mearsheimer analyzed the ongoing Russia-Ukraine war. He argued that the conflict is primarily the result of NATO expansion, contending that the expansionist NATO and EU policies from 2008–2022—which were driven by liberal ideology rather than a containment strategy—caused Russia to “scream bloody murder.” Yet, despite Vladimir Putin’s repeated warnings, NATO continued to move east, leading to a dramatic Russian reaction. The response to Mearsheimer’s visit was positive overall, with the audience applauding as he stepped away from the podium. 

The NDISC’s speaker series continues on February 20 with “China’s Gambit: The Calculus of Coercion,” a lecture by Professor Ketian Zhang of George Mason University.

Eric Gordy is a sophomore studying economics and political science. When he’s not helping Shri with econ homework in Remick or fantasizing about the return of the British Empire, you can reach him at

Elliot Anderson is a junior studying biological sciences and political science. He is committed to Minnesota independence and the return to regional dialects. For inquiries about this mission send a message to

Photo Credit: NDISC

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