The top-secret laboratory in Los Alamos, New Mexico, opened in April 1943 with J. Robert Oppenheimer as its scientific director. Just 27 months later, Oppenheimer and his colleagues were ready to test an atomic weapon. Everyone at Los Alamos in a position to have an informed opinion agreed that without Oppenheimer's extraordinary leadership, atomic bombs would not have been completed in time to be used during the war. That was both a matter of pride and a heavy burden for "the father of the atomic bomb."
Another Los Alamos scientist recalled that Oppenheimer "was present in the laboratory or in the seminar rooms when a new effect was measured, when a new idea was conceived . . . . His continuous and intense presence . . . produced a sense of direct participation in all of us."
Oppenheimer was also present when fellow scientists discussed potential uses of the bomb. By the end of 1944, it was clear that the war in Europe would soon be over. A number of the scientists at Los Alamos began to voice their growing ethical qualms about the continued development of the "gadget."
Oppenheimer argued that the war should not end without the world knowing about this primordial new weapon. If the gadget remained a military secret, then the next war would almost certainly be fought with atomic weapons, and they would be used in a surprise attack. The scientists had to forge ahead, he explained, to the point where it could at least be tested.