continental ballistic missile (ICBM),61 in began early in 1946, when the Air Materiel Command of the Army Air Forces awarded a study contract for a long-range missile to Consolidated Vultee Aircraft Corporation (Convair), of San Diego. By mid-year a team of Convair engineers, headed by Karel J. Bossart, had completed a design for "a sort of Americanized V–2," called “HIROC,” or Project MX-774. Bossart and associates proposed a technique basically new to American rocketry (although patented by Goddard and tried on some German V–2s)—controlling the rocket by swiveling the engines, using hydraulic actuators responding to commands from the autopilot and gyroscope. This technique was the precursor of the gimbaled engine method employed to control the Atlas and other later rockets. In 1947, the Truman administration and the equally economy-minded Republican 80th Congress confronted the Air Force with the choice of having funds slashed for its intercontinental manned bombers and interceptors or cutting back on some of its advanced weapons designs. Just as the first MX-774 test vehicle was nearing completion, the Air Force notified Convair that the project was canceled. The Convair engineers used the remainder of their contract funds for static firings at Point Loma, California, and for three partially successful test launches at White Sands, the last on December 2, 1948.62
From 1947 until early 1951 there was no American project for an intercontinental ballistic missile. The Soviet Union exploded her first atomic device in 1949, ending the United States' postwar monopoly on nuclear weapons. President Harry S. Truman quickly ordered the development of hydrogen-fusion warheads on a priority basis. The coming of the war in Korea the next year shook American self-confidence still further. The economy program instituted by Secretary of Defense Louis Johnson ended, and the military budget, including appropriations for weapons research, zoomed upward. The Army began its work leading to the Redstone, while the Air Force resumed its efforts to develop an intercontinental military rocket. In January 1951 the Air Materiel Command awarded Convair a new contract for Project MX-1593, to which Karel Bossart and his engineering group gave the name "Project Atlas."63 Yet the pace of the military rocket program remained deliberate, its funding conservative.
A series of events beginning in late 1952 altered this cautious approach. On November 1, at Eniwetok Atoll in the Pacific, the Atomic Energy Commission detonated the world's first thermonuclear explosion, the harbinger of the hydrogen bomb. The device weighed about 60,000 pounds, certainly a much greater weight than was practicable for a ballistic missile payload. The next year, however, as a result of a recommendation by a Department of Defense study group, Trevor Gardner, assistant to the Secretary of the Air Force, set up a Strategic Missiles Evaluation Committee to investigate the status of Air Force long-range missiles. The committee, composed of nuclear scientists and missile experts, was headed by the famous mathematician John von Neumann. Specifically, Gardner asked the committee to make a prediction regarding weight as opposed to yield in nuclear payloads for some six or seven years hence. The
