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In 1938 many people feared that Hitler would build an atomic bomb after word spread that German scientist had split the uranium atom (fission). However, one of Hitlers mistakes was his persecution of Jewish scientists. This persecution resulted in numerous scientists seeking asylum in the United States. One such scientist was Albert Einstein. Einstein, abandoning his belief in pacifism, urged then president Franklin Roosevelt to develop an atomic bomb before Hitler did. Eventually Roosevelt agreed and the United States attempt at building the atomic bomb was codenamed The Manhattan Project.

The Manhattan Project was the project to develop the first nuclear weapon (atomic bomb) during World War II by the United States, the United Kingdom, and Canada. Formally designated as the Manhattan Engineer District (MED), it refers specifically to the period of the project from 19411946 under the control of the U.S. Army Corps of Engineers, under the administration of General Leslie R. Groves. The scientific research was directed by American physicist J. Robert Oppenheimer.

The project succeeded in developing and detonating three nuclear weapons in 1945: a test detonation of a plutonium implosion bomb on July 16 (the Trinity test) near Alamogordo, New Mexico; an enriched uranium bomb code-named "Little Boy" on August 6 over Hiroshima, Japan; and a second plutonium bomb, code-named "Fat Man" on August 9 over Nagasaki, Japan.

The project's roots lay in scientists' fears since the 1930s that Nazi Germany was also investigating nuclear weapons of its own. ...more

Fine

It was about development of Atom Bomb