He studied politics at Princeton University, and international relations at Oxford under a Rhodes scholarship. He has published three books on American foreign and national security policies, The Obama Doctrine: American Grand Strategy Today (New York: Oxford University Press, 2015), Hard Line: The Republican Party and U.S. Foreign Policy since World War II (Princeton, NJ: Princeton University Press, 2010), and Reluctant Crusaders: Power, Culture, and Change in American Grand Strategy (Princeton, NJ: Princeton University Press, 2006.) His current research focus is on the relationship between party politics, presidential leadership, American conservatism, and U.S. foreign policy strategies.