January 1950 President Truman ordered the Atomic Energy Commission (AEC) to develop the hydrogen bomb (H-bomb). The hydrogen, or thermonuclear, bomb uses the same process that the sun uses to release tremendous energy. In the H-bomb, the nuclei of two light atoms (usually hydrogen) are fused together to form a heavier atom, helium. A fission reaction, one where a heavier atom is split into lighter ones, generates the energy to trigger the fusion reaction. Edward Teller had begun theoretical work on the hydrogen bomb at Los Alamos Scientific Laboratory during World War II. After the war, he lobbied scientists, congressmen, the military, and the AEC to begin work on the hydrogen bomb. The General Advisory Committee of the AEC, chaired by Robert Oppenheimer, condemned the H-bomb on moral grounds as a "weapon of genocide." The committee also believed that developing the H-bomb would lead the United States into an arms race with the Soviet Union. The AEC and the President's advisors, however, were undecided. In January 1950, President Truman summoned his advisors and asked them one question, "Can the Soviets do this?" His advisors believed the Soviets could eventually develop a hydrogen bomb, and Truman decided to go ahead with its development. This decision triggered the establishment and/or expansion of three U.S. sites: Savannah River Plant, Los Alamos Scientific Laboratory, and Lawrence Livermore Laboratory. The United States exploded the H-bomb in November 1952 at the Eniwetok Atoll in the Pacific.