BOMBING OF HIROSHIMA AND NAGASAKI

 Since 1942, more than 100,000 scientists of the Manhattan Project had been working on the bomb’s development. At the time, it was the largest collective scientific effort ever undertaken. It involved 37 installations across the US, 13 university laboratories and a host of prestigious participants such as the Nobel prizewinning physicists Arthur Holly Compton and Harold Urey. Directed by the Army's chief engineer, Brigadier General Leslie R. Groves, the Manhattan Project was also the most secret wartime project in history.On August 6, 1945, during World War II (1939-45), an American B-29 bomber dropped the world’s first deployed atomic bomb over the Japanese city of Hiroshima. The explosion wiped out 90 percent of the city and immediately killed 80,000 people; tens of thousands more would later die of radiation exposure. Three days later, a second B-29 dropped another A-bomb on Nagasaki, killing an estimated 40,000 people. Japan’s Emperor Hirohito announced his country’s unconditional surrender in World War II in a radio address on August 15, citing the devastating power of “a new and most cruel bomb.''

A survivor described the damage to people:

The appearance of people was . . . well, they all had skin blackened by burns. . . . They had no hair because their hair was burned, and at a glance you couldn't tell whether you were looking at them from in front or in back. . . . They held their arms bent [forward] like this . . . and their skin - not only on their hands, but on their faces and bodies too - hung down. . . . If there had been only one or two such people . . . perhaps I would not have had such a strong impression. But wherever I walked I met these people. . . . Many of them died along the road - I can still picture them in my mind -- like walking ghosts.

The Manhattan Project

Even before the outbreak of war in 1939, a group of American scientists–many of them refugees from fascist regimes in Europe–became concerned with nuclear weapons research being conducted in Nazi Germany. In 1940, the U.S. government began funding its own atomic weapons development program, which came under the joint responsibility of the Office of Scientific Research and Development and the War Department after the U.S. entry into World War 1. The U.S. Army Corps of Engineers was tasked with spearheading the construction of the vast facilities necessary for the top-secret program, codenamed “The Manhattan Project ” (for the engineering corps’ Manhattan district).