Hiroshima Bombed: Atomic Warfare Changes Everything

A single bomb erased a city. At 8:15 a.m. on August 6, 1945, the B-29 bomber Enola Gay released a uranium weapon code-named "Little Boy" over the center of Hiroshima, Japan. The bomb detonated 1,900 feet above Shima Surgical Clinic, missed its aiming point at the Aioi Bridge by about 800 feet, and produced a blast equivalent to 16,000 tons of TNT. Between 70,000 and 80,000 people died instantly. Tens of thousands more would die in the following weeks and months from burns, radiation sickness, and injuries. The decision to use atomic weapons had been debated within the highest levels of the American government for months. President Truman, who had learned of the bomb's existence only after taking office in April, approved its use against Japanese cities after the successful Trinity test in New Mexico on July 16. The stated rationale was to force Japan's surrender without an invasion of the home islands, which military planners estimated could cost hundreds of thousands of American casualties and millions of Japanese lives. Hiroshima was chosen from a short list of targets that had been deliberately spared from conventional bombing so the atomic weapon's effects could be clearly measured. The city was a major military headquarters and embarkation port with a population of roughly 350,000. Most residents had no warning. Japanese radar detected the small formation of three B-29s but did not trigger a full alert, since small groups were usually reconnaissance flights. The all-clear had sounded just minutes before the bomb fell. The physical destruction was nearly total within a one-mile radius. Fires consumed 4.4 square miles of the city. People near the hypocenter were vaporized, leaving only shadows burned into concrete. Survivors, known as hibakusha, suffered radiation effects for decades. Three days later, a second bomb was dropped on Nagasaki. Japan announced its surrender on August 15. The atomic age had begun with a flash visible for miles and a mushroom cloud that rose 40,000 feet above what had been, moments earlier, a living city.