John Gans, PhD, who works and teaches at the University of Pennsylvania, is a historian of U.S. foreign policy, national security and politics. He has served as chief speechwriter to the Secretary of Defense at the Pentagon, at the Treasury Department, on Capitol Hill in the Office of the Speaker of the U.S. House of Representatives, and as a Navy reserve officer. His new book, White House Warriors: How the National Security Council Transformed the American Way of War, is available now.