His academic work focuses on international-relations theory, power politics, empires and hegemony, and international order. He has also written on the relationship between popular culture and world politics.
His first book, The Struggle for Power in Early Modern Europe: Religious Conflict, Dynastic Empires, and International Change (Princeton University Press, 2009), won the International Security Studies Section (ISSS) Best Book Award for 2010. His second book, Exit from Hegemony: The Unravelling of American Global Order (Oxford University Press, 2020), co-authored with Alex Cooley, explores the contentious politics of international order. A new co-edited volume, Undermining the Hegemon: The Politics of Goods Substitution, is forthcoming with Cambridge University Press.
He has held fellowships at Stanford University’s Center for International Security and Cooperation and at the Ohio State University’s Mershon Center for International Studies. During 2009-2010, he worked in the U.S. Department of Defense as a Council on Foreign Relations International Affairs Fellow. From 2014-2018, he was the lead editor of International Studies Quarterly.
He co-hosts a podcast, with Patrick Thaddeus Jackson, which is pretty much what it sounds like.
He contributes to a group weblog: Lawyers, Guns and Money. He has also written for such non-academic outlets as Foreign Affairs, Foreign Policy, and The Atlantic. He is particularly interested in how progressives should think about, and pursue, foreign policy.