The relationship existing from the end of World War II between the USA and its allies on one side (the West) and the former Soviet Union and its allies on the other (the East). After the war the USA and the Soviet Union emerged as superpowers based on opposing ideologies, with global interests. The USA had a stake in the security of Western Europe, while the Soviet Union extended its influence over the countries of the Eastern bloc, despite Eastern European discontent, leading to the Yugoslav break with Stalin in 1948 and Soviet repression of dissidents in Poland, Czechoslovakia, and elsewhere. Both sides possessed increasing nuclear capabilities. The bipolar split in world politics became evident in the alliance systems of NATO and the Warsaw Pact. The period of mutual distrust and rivalry that ensued, characterized by ideological differences, the dissemination of propaganda, the build-up of arms, military threat, and occasional misunderstandings and crises, became known as the Cold War. Each side built up its nuclear arsenals (see arms race) and attempted to extend its sphere of influence in the developing world. However, the rigid polarization of the first period of the Cold War was broken down in the early 1960s by an ideological split between the communist regimes of China and the Soviet Union, and the formation of the Non-Aligned Movement, an attempt to remain independent from both East and West. During the 1970s there was a period of détente when relations improved, only to deteriorate because of the Soviet invasion of Afghanistan (1979), which triggered what many called the second Cold War. However, the later 1980s saw the rise of glasnost and perestroika in the Soviet Union, progress in arms agreements, the withdrawal of the Soviet army from Afghanistan (1989), the demise of communism in the Eastern bloc, the reunification of Germany in 1990, and the disbanding of the Warsaw Pact in the same year. In 1991 the Soviet Union itself ceased to exist, as the constituent republics asserted their independence. In 1997 a formal alliance between Russia and NATO was signed. However, Russia continued to express dismay at certain aspects of NATO policy and criticized international actions in the former Yugoslavia. Nevertheless, with the demilitarization of East–West relations and prospects of greater cooperation between the two sides, the East–West balance of power has ceased to be an overriding factor in shaping international relations.
Subjects: World History.