Now that the cold war is long over, our thinking of nuclear weapons and the role that they play in international security has undergone serious changes.

The emphasis has shifted from superpower confrontation to nuclear proliferation, spread of weapon materials, and to the dangers of countries developing nuclear weapon capability under a cover of a civilian program. At the same time, the old cold-war dangers, while receded, have not disappeared completely. The United States and Russia keep maintaining thousands of nuclear weapons in their arsenals, some of them in very high degree of readiness. This situation presents a serious challenge that the international community has to deal with.