This is a list of the three generations of ICBMs produced and deployed by the United States during the Cold War, with a fourth generation ICBM being deployed in small numbers at the end of the Cold War in 1991.Development of Intercontinental ballistic missile (ICBM) technology as an outgrowth of the World War II V-2 rocket technology developed by Germany, and the mating of nuclear weapon technology developed by the United States created an entire new method of warfare. Due to their great range and firepower, in an all-out nuclear war, land-based ICBMs would carry most of the destructive force, with long-range, nuclear-armed bombers and Submarine-launched ballistic missiles carrying the remainder. These three components were collectivity referred to as the United States nuclear triad. The U