The time for completing this book was made available thanks to the Hoover Institution at Stanford University, which hosted me as a W. Glenn Campbell and Rita Ricardo-Campbell National Fellow and the Edward Teller Fellow for academic year 2013–2014. The Hoover Institution provided, in addition to time and financial support, a delightful environment for work. Conversations with other National Fellows were a particularly enjoyable—and useful—part of the environment. I thank in particular (but without limitation as to others) Sarah Paine of the US Naval War College, Paul Rahe of the Departments of History and Political Science of Hillsdale College, and Gaurav Sood of the McCourt School of Public Policy at Georgetown. Among permanent Stanford faculty and Hoover fellows who shared valuable insights relevant to this work, I thank Norman Naimark of the Department of History, Ian Morris of the Department of Classics, Don Emmerson and Moria Paz of the Freeman Spogli Institute, Jenny Martinez of the Law School, Hoover Research Fellows Paul R. Gregory and Bert Patenaude, and Hoover Senior Fellows Thomas H. Henriksen, John B. Dunlop, and Abraham D. Sofaer. My time at the Hoover Institution was further enriched by conversations with National Security Fellows (2013–14) Colonel Eric Shirley (USA), Colonel Roy Collins (USAF), Lieutenant Colonel Matthew Atkins (USAF), Commander Steve Newland (USN), and Colonel Thomas Womble (USA National Guard). The National Fellows staff secretary, Heather Campbell, provided unceasingly cheerful support and guidance.