When the Cold War ended, much of the world seemed to breathe a momentary sigh of relief. The greatest existential threat in human history, that of an all-out nuclear holocaust, appeared to have practically vanished overnight. Soon it became clear that we were not quite out of the woods yet. State-versus-state tensions between the United States and Russia did not completely dissipate. New nuclear powers, like Pakistan and North Korea, emerged publicly, and suspicions about potential future nuclear powers abound. The threat of nuclear terrorism, something which had been discussed publicly since the late 1960s, took on a new relevance in the face of threats about loose fissile material and extremist terrorism. And the global effects of even a regional nuclear exchange, such as one in South Asia, became more acutely appreciated.