In each decade of the nuclear age, philosophers have provided critical reflections on the nature, use, and consequences of nuclear weapons. Frequently, these reflections have addressed the morality of producing, testing, deploying, and using nuclear weapons. Already, these philosophical reflections have passed through four phases and are now entering a fifth phase. The first phase stretches from the atomic bombing of Hiroshima to the above ground nuclear tests at Bikini Atoll. From the initial use of atomic weapons in 1945 to the testing of the hydrogen bomb in 1952, the United States held a virtual monopoly. (The Soviet Union tested its first atomic weapon in 1949, and the United States progressed not only to the development of the hydrogen bomb, but also to a miniaturization of nuclear weapons that spawned even more tactical nuclear weapons than the eventual strategic arsenals of the superpowers.) During the 1950s and 1960s, the second phase shifts to a focus on the above ground testing of the hydrogen bomb, as well as the post war tension between the United States and the Soviet Union. The third phase addresses increasing shifts during the 1970s and 1980s to counterforce weapons and nuclear war fighting strategies. The fourth phase responds to the dissolution of the Soviet Union in 1991 and to the problems of nuclear proliferation and nuclear deterrence in the post Cold War world, culminating with a critique of the renewal of Star Wars in 2001 under the guise of ballistic missile defense. The first decade of the twenty first century ushers in not only the purported