摘要：Is nuclear deterrence an important element in US and allied security? If so, how many and what types of nuclear weapons are adequate for this purpose? These questions get to the heart of contemporary and decadesold nuclear policy debates, because most US nuclear policy initiatives are justified or criticized according to judgments regarding their potential effects on the US capacity to deter opponents. Most recently, the capability of our forces to help assure allies via extended deterrence, including the “nuclear umbrella,” has been emphasized as a metric for US forces.1 Using deterrence, extended deterrence, and assurance as a basis for judging the adequacy of US nuclear forces is appropriate because they are primary national security goals.
