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  President Franklin D. Roosevelt signs executive order 9066 allowing the United States military to define areas as exclusionary zones
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  The development of the first atomic bomb is signed into agreement between the Prime Minister of Great Britain, Winston Churchill, and President Franklin D. Roosevelt
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  The first nuclear chain reaction is produced at the University of Chicago in the Manhattan Project
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  he Jefferson Memorial in Washington, D.C. is dedicated on the 200th anniversary of Thomas Jefferson's birth
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  The G.I. Bill of Rights is signed into law, providing benefits to veterans
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  Franklin D. Roosevelt became the 32nd president of the United States
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  President Roosevelt dies suddenly
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  Truman becomes president after Roosevelts sudden death.
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  President Harry S. Truman gives the go-ahead for the use of the atomic bomb with the bombing of Hiroshima.
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  United States Senate approves the entry of the United States into the United Nations.
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  Truman establishes the President's Committee on Civil Rights to investigate the status of civil rights in the United States
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  authorizes $15 billion in aid for 16 countries.
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  The Twenty-second Amendment to the United States Constitution, limiting Presidents to two terms, is ratified.
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  expires after distributing more than $13.3 billion USD in foreign aid to rebuild Europe.
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  Eisenhower becomes the 34th President of the United States.
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  Nuclear testing at the Nevada Test Site, United States conducts its first and only nuclear artillery test.