Sean Henninger

Sean Henninger is a PhD candidate in Political Science at Boston College, specializing in international security and grand strategy. He expects to defend his dissertation, Sphere of Influence Agreements in British and American Diplomacy, 1895-1945, in July 2026; the project examines when and why great powers shift from accommodating to confronting a rival's sphere, drawing on archival research in British and American diplomatic history. Previously, Sean worked as a Summer Associate at the RAND Corporation, where he co-authored a forthcoming report on military energy and water resilience for theater operations, and as a Research Assistant at the Yorktown Institute on U.S. grand strategy and great power competition; he has also served as a Contributing Fellow at Defense Priorities, where his research focused on advancing realism and restraint in American grand strategy. Sean has taught more than 200 students across ten courses at Boston College in international relations, American politics, and political theory. He has published commentary, a forthcoming book review, and his research has been accepted to MPSA, ISA, NPSA, and the Cato Institute's Junior Scholars Symposium. He holds a BA in Political Science with Honors from the University of Tennessee, where he was a Howard H. Baker Center for Public Policy Scholar. He is a 2026-27 Hans J. Morgenthau Fellow (Cohort 7) at the O'Brien Notre Dame International Security Center.