This book examines how deterrence, coercion and modernization theory has informed U.S. policy, addressing why former Defense Secretary Robert McNamara’s famous description of the Vietnam War as the “social scientist’s war” is so accurate. By tracing the evolution of ties between social scientists and the government beginning in World War I and continuing through the Second World War and the early Cold War, the narrative highlights the role of institutions like the RAND Corporation, the Social Science Research Council and MIT’s Center for International Studies that facilitate these ties while providing a home for the development of theory. The author compares and contrasts the ideas of Bernard Brodie, Herman Kahn, Albert Wohlstetter, Thomas Schelling, Gabriel Almond, Lucian Pye and Walt Rostow, among others, and offers a cautionary tale concerning the difficulties and problems encountered when applying social science theory to national security policy.