Although Nike was created in response to Soviet efforts to design and deploy long-range bomber aircraft during the early years of the Cold War, Soviet military strategy soon changed. By the late 1950s, fearing that their manned aircraft would be too vulnerable to attack by American interceptor aircraft armed with rockets and missiles, the Soviet Union focused more of its attention on developing ICBMs or Intercontinental Ballistic Missiles against which there existed, at that time, no effective defense. The Soviet long-range strategic bomber force continued to operate throughout the Cold War. However, these forces never achieved the size or capabilities of their American counterpart, the U.S. Air Force's Strategic Air Command (SAC).
The shifting nature of the Soviet threat meant that the air defense role, for which Nike was originally intended, became relatively less critical as time passed. Defense dollars were needed for other projects (including the development of American ICBMs and potential missile defenses) and also to fund the rapidly growing war in Vietnam. As a result, beginning in the mid 1960s, the total number of operational Nike bases within the continental U.S. was fairly steadily reduced, on an almost annual basis. All Nike Ajax sites in the continental United States were closed down by 1964. Closures of select Nike Hercules sites began during the mid 1960s.
During 1974, all remaining operational sites within the nationwide Nike air defense system were inactivated. Army Air Defense Command (ARADCOM) which administered this system was closed down shortly thereafter. The deactivation of the nationwide Nike missile system signaled the end of one of the nation's most significant, highly visible and costly Cold War air defense program.
Despite the termination of the nationwide Nike program in the United States, Nike missiles remained operational at a small number of sites in southern Florida and in Alaska for several more years. Nike missiles also remained operational with U.S. forces in Europe and the Pacific, and with the armed forces of many U.S. Allies overseas. Although no longer in the U.S. inventory, more than four decades after the first Nike missile became operational in the U.S., Nike Hercules missiles were deployed by the armed forces of Italy, Greece, Turkey and South Korea.