The atomic bomb.

"Then a tremendous flash of light cut across the sky . Mr. Tanimoto has a distinct recollection that it traveled from east to west, from the city toward the hills. It seemed like a sheet of sun. John Hersey, from Hiroshima, pp8 On August 6, 1945, the world changed forever. On that day the United States of America detonated an atomic bomb over the city of Hiroshima. Never before had mankind seen anything like. Here was something that …

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