During the Cold War, policy makers and scholars worried that nuclear weapons would proliferate widely—yet, after all this time, there remain relatively few nuclear powers. Today, the nonproliferation regime faces challenges from unrecognized nuclear states like North Korea and other rogue regimes like Iran. The international community must continue to limit the spread of nuclear weapons, while the United States works to assure nuclear-proliferation compliant allies of the integrity of the US nuclear umbrella.
