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  On this day the Chicago Pile-1 was invented by Italian physicist Enrico Fermi.
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  The first artificial kidney machine was developed by Willem Kolff used to detect kidney failure.
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  Harry S. Truman won the election for president against Thomas E. Dewey as a Democrat. He took office after the death of Franklin D. Roosevelt.
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  Began when the Soviet-backed North Korean People's Army invaded its pro-Western neighbor to the south.
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  This amendment set term limits for the president so he could now only serve two terms.
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  Also known as the European Recovery Program, was a U.S. program providing aid to Western Europe following the devastation of World War II in hopes to help recover those families and lives that lost many things.
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  US scientists William Shockley, Walter Brattain and John Bordeen invented the world's first transistor radio which was made portable and gives access to communication.
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  Soldiers from North Korean Army poured across the 38th parallel and sparked this war. This was the first invasion during Cold war.
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  This act (INA) was passed to make it harder for possible communist and soviet spies to gain citizenship in the United States by U.S.C. or United States Code.
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  President Harry Truman announces news of the development of the hydrogen bomb.
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  Jonas Salk announces a new vaccine to prevent and help polio.