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Today in History: Einstein and Szilard warn Roosevelt about atomic bombs

8/2/2025

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Summary

Story summary

On August 2, 1939, physicist Leo Szilard wrote a letter, signed by Albert Einstein, to President Franklin D. Roosevelt. The letter warned that Germany might develop atomic bombs and urged the U.S. to initiate its own nuclear program. This communication prompted Roosevelt to take action, ultimately leading to the Manhattan Project and the development of atomic weapons.

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Story summary

On August 2, 1939, physicist Leo Szilard wrote a letter, signed by Albert Einstein, to President Franklin D. Roosevelt. The letter warned that Germany might develop atomic bombs and urged the U.S. to initiate its own nuclear program. This communication prompted Roosevelt to take action, ultimately leading to the Manhattan Project and the development of atomic weapons.