NATO and the Warsaw PactDuring the Cold War most of western Europe was aligned with the United States through membership in the North Atlantic Treaty Organization (NATO), while the Soviet Union maintained garrisons in its satellites under the terms of the Warsaw Pact.
alliance, In international politics, a union for joint action of various powers or states. Examples include the alliance of the European powers and the U.S. against Germany and its allies during World War II and the alliance of the NATO states against the Soviet Union and its allies during the Cold War. Many alliances rest on the principle of collective security, through which an attack on one member is considered an attack on all members. Major alliances formed after World War II include the ANZUS Pact, the Arab League, ASEAN, the Organization of American States, the Southeast Asia Treaty Organization, and the Warsaw Pact.