WikipediaExtracts:Einstein–Szilárd letter
Extracted from Wikipedia --
A letter written by Leo Szilard and signed by Albert Einstein on August 2, 1939, was sent to President of the United States Franklin D. Roosevelt. Szilard consulted with fellow Hungarian physicists Edward Teller and Eugene Wigner, warning that Germany might develop atomic bombs and suggested that the United States start its own nuclear program.
Despite the importance of the letter the US did not kick start their atomic bomb programme for another three years, and this was through other means.
