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Key Issues Nuclear Weapons History Pre Cold War Manhattan Project

Manhattan Project

The Manhattan Project was a secret military project created in 1942 to produce the first US nuclear weapon. Fears that Nazi Germany would build and use a nuclear weapon during World War II triggered the start of the Manhattan Project, which was originally based in Manhattan, New York.

US physicist Robert Oppenheimer and General Leslie R. Groves served as directors of this project, which recruited some of the best US scientists, engineers and mathematicians. A number of European scientists, including Albert Einstein, Enrico Fermi, and Leo Szilard, also participated in the Manhattan Project.

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Under the auspices of the Manhattan Project, three main research and production facilities were established at Oak Ridge, Tennessee; at Hanford, Washington; and at Los Alamos, New Mexico. The Oak Ridge Laboratories provided uranium-235 and Hanford produced weapons-grade plutonium. The Los Alamos Laboratory became the site for assembling nuclear weapons.

Los Alamos produced four weapons, two of which, Little Boy and Fat Man, were used against Japan in August 1945. The Manhattan Project officially ended in 1946 when it became part of the Atomic Energy Commission (AEC).

The decision to drop the atomic bombs on the cities of Hiroshima and Nagasaki is one of the most controversial issues of the 20th century. Many modern historians have criticized the commonly held perceptions that the bomb shortened the war, saved American lives and prevented USSR’s sharing in the post-war administration of Japan (see, for example, Hiroshima’s Shadow edited by Kai Bird & Lawrence Lifschultz ). In 1995, on the 50th anniversary of the bombing, an exhibit designed to commemorate the event resulted in unprecedented controversy for the Smithsonian Institution . The American Legion and other veteran’s organizations successfully lobbied against the inclusion of quotes from a number of notables including Dwight D. Eisenhower that questioned the necessity of the bomb’s use.

The debate has not subsided. The decision to drop the first atomic bomb on Japan will remain relevant to our joint human experience forever. Important questions remain: Did it have to happen? Will it happen again in an even more catastrophic way? What do the first human experiences with nuclear power say about humanity’s ability to control its most dangerous creation?