Arms control, a term popularized in the early 1960s, refers to the voluntary limitation or reduction of weapons and their means of delivery, between and among countries, through negotiation. It is distinct from disarmament, which seeks to eliminate, also by international agreement, the means by which countries wage war. While arms control compiled a mixed record during the post-World War II era, revolutionary changes in international politics during the early 1990s-most especially the collapse of the USSR and the end of the Cold War-have opened up promising new opportunities for radical reductions in the nuclear and conventional weapons arsenals of the major powers.