Greg's guest is Dr. Terence Roehrig. Dr. Roehrig is a Professor in National Security Affairs and the Director of the Asia-Pacific Studies Group at the U.S. Naval War College in Newport, Rhode Island. He is also a Research Fellow at the Kennedy School at Harvard University in the International Security Program and the Project on Managing the Atom. He is the author of two forthcoming books: Japan, South Korea, and the U.S. Nuclear Umbrella: Extended Deterrence and Nuclear Weapons in the Post-Cold War World (Columbia University Press) and South Korea's Rise in World Affairs: Power, Economic Development and Foreign Policy.