His research lies at the intersections of international relations and political theory. He has published work on the historical development and transformation of state sovereignty, 17th century and 20th century political philosophy, space weaponization and security, global dimensions of indigenous politics and hermeneutics. He is the author of Captives of Sovereignty (Cambridge University Press, 2011), and he has published peer reviewed articles in Political Theory, International Studies Quarterly, Constellations, Review of International Studies, Journal of International Political Theory, Polity, Social Sciences Quarterly and the Journal of Political Science Education. His current research focuses on pacification and anti-state violence. He is co-editor of the journal Global Constitutionalism.