US Strategic and Defensive Missile Systems 1950–2004

From the 'Introduction'

The development of the atomic bomb dramatically changed military strategic planning, and outmoded all existing defensive systems in use at the beginning of World War II. Postwar American defensive strategy changed from defense against potential invasion to defense against potential total destruction. The new defensive strategies were centered on ways to defend against the delivery of the atomic bomb. By the 1950s, the United States had developed a series of defensive antiaircraft missile systems that were capable of delivering conventional and nuclear explosives against massed bomber formations. Simultaneously, the United States and the Soviet Union developed a series of offensive missile systems that could deliver nuclear payloads against ground targets located on distant continents. Both the United States and the Soviet Union parlayed the implied use of these weapons as a deterrent against aggression by the other power – a “defensive” role for these potent offensive weapons.