The first test of the atomic bomb was at the Trinity bomb site in central New Mexico. On July 16, 1945 the first atomic bomb was detonated in the Jornada del Muerto desert about 35 miles southeast of Socorro, New Mexico near the Los Alamos research facility. Dr. J. Robert Oppenheimer, director of the project, watched the mushroom cloud rise into the New Mexico sky. “Now I am become death, destroyer of worlds,” he uttered, reciting a passage from an ancient Hindu text. News of the successful test was relayed to President Harry S. Truman, who was meeting with Soviet leader Joseph Stalin in Potsdam to discuss the postwar world.

The U.S. hoped that possession of the atomic bomb would be America’s trump card in dealing with the Soviets after the war. Use of the weapon against the Japanese cities of Hiroshima and Nagasaki in August 1945 demonstrated the destructive force of the atomic bomb. America's monopoly in having the bomb did not last long. By 1949, the Soviet Union had developed their own atomic bomb, which was the start of the nuclear arms race between the U.S. and Soviet Union.

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