The Letter Reached Roosevelt

On 11 October 1939, economist Alexander Sachs met President Franklin D. Roosevelt and delivered a letter signed by Albert Einstein. The letter had been drafted with physicist Leo Szilard and dated in August. Sachs had promised to put the warning before Roosevelt in person; the outbreak of war in Europe had delayed the meeting for weeks.

The warning began with a scientific possibility. Work on uranium and chain reactions, Einstein wrote, suggested that large amounts of energy might be released and that extremely powerful bombs could be built. The letter also warned that Germany might be pursuing such research. Szilard and other physicists feared that German access to uranium could make the prospect more than theoretical.

Sachs did not simply hand Roosevelt the letter and leave him to decipher its scientific argument. He had prepared a cover letter and briefed the president on the main points. He first described peaceful uses of atomic energy, including power and medicine, then turned to the destructive possibility. Sachs believed that the technical case needed an interpreter; he later said that no scientist could “sell it” to Roosevelt.

Roosevelt initially remained noncommittal and worried about where the money for research would come from. He asked Sachs to come back the next morning. At breakfast on 12 October, Sachs pressed the case again. “Alex,” the president said, “what you are after is to see the Nazis don’t blow us up.” “Precisely,” Sachs replied. Roosevelt then called in his military aide, Edwin M. “Pa” Watson, and said, “This requires action.”

The meetings did not produce an immediate bomb program. On 19 October, Roosevelt wrote to Einstein that he had set up a committee, including Sachs and representatives of the Army and Navy, to study uranium.

The letter had asked the administration to take seriously the possibility of a weapon Germany might build. Its delivery did not settle the question of what the United States would do, or how far it would go. It did put the warning directly before the president, with Sachs translating the physics into the political question Roosevelt understood: whether the United States could risk letting Hitler get such a weapon first.