Welcome! I am an Assistant Professor of Political Science at Boston College. In the 2025-2026 academic year, I am a Stanton Nuclear Security Fellow in the Center for Nuclear Security Policy at the MIT Security Studies Program. Previously, I was a Global Innovation Program Postdoctoral Fellow at the University of Pennsylvania’s Perry World House and a Hans J. Morgenthau Predoctoral Fellow at the Notre Dame International Security Center.

I specialize in International Relations, with a focus on questions related to grand strategy, alliance politics, and political violence. My first book project examines grand strategy and its outcomes in the context of military alliances. It argues that a leading power may fail to promote its desired military capabilities among smaller allies because the demands of its grand strategy clash with the risks presented to the allies by a hostile great power that is scrutinizing the alliance’s actions. My second book project, co-authored with John Mearsheimer, undertakes a theoretically grounded investigation on the question of whether the United States—which has been the sole “regional hegemon” in the international system since the late 19th century—should fear the rise of another regional hegemon in Europe or East Asia.

My broader research interests center on topics such as preventive war, the role of nuclear weapons in grand strategy, the relationship between power politics and international norms, and the performative uses of violence by state and nonstate actors. Some of my research has been published or is forthcoming in outlets such as the American Political Science Review, International Studies Quarterly, European Journal of International Security, Texas National Security Review, Contemporary Security Policy, and Political Science Quarterly.

Policy analysis and commentary based on my research can be found in forums like The Diplomat, Foreign Affairs, Foreign Policy, and the Washington Quarterly, as well as podcasts hosted by the Cato Institute and War on the Rocks.

My research has been supported by the Smith Richardson Foundation, the Charles Koch Foundation, and the Korea Foundation for Advanced Studies, as well as the Center for East Asian Studies and the Pearson Institute for the Study and Resolution of Global Conflicts at the University of Chicago, among others.

Before beginning my academic career, I served as the personal interpreter to South Korea’s Chairman of the Joint Chiefs of Staff. In this capacity, I assisted the Chairman during all interactions with English-speaking foreign partners, including the Commander of the U.S. Forces Korea (CDRUSFK), Commander of the U.S. Pacific Command (CDRUSPACOM), and the Chairman of the U.S. Joint Chiefs of Staff (CJCS).

I received a Ph.D. in Political Science from the University of Chicago in 2022. I also hold an M.A. in Political Science from the University of Chicago and a B.A. in International Studies and Political Science, summa cum laude, from Korea University.

Contact: joshua.byun@bc.edu