The U.S.–Japan alliance and the future of extended deterrence

Abstract North Korea's redoubled efforts to perfect its nuclear weapon and missile capabilities have focused attention on the issue of deterrence in Japan, as some political leaders question whether their country's defense posture and its alliance with the United States will continue to be adequate to deter potential North Korean coercion or aggression. China's nuclear weapons and military modernization programs are causing similar concerns. The key issue, however, is how well deterrence and extended deterrence (underwritten by the United States) will function in East Asia, given the dramatic changes in the regional security environment and recent U.S. arms-control initiatives. Precisely when Tokyo is placing greater emphasis on homeland defense issues, Washington is emphasizing maximum flexibility to fight insurgencies and prevent nuclear terrorism around the world. While Japan is taking keener interest in the U.S. nuclear umbrella, the United States is planning for deeper cuts in its nuclear arsenal. Th...