Einstein Writes A Letter To Roosevelt, October 11, 1939

Today in 1939, US President Franklin Roosevelt was presented a letter written to him by Albert Einstein. This letter, written more than two years before the United States became involved in the Second World War, created the first spark of an idea that would become the Manhattan Project, the program which lead to the development of an atomic bomb.

In the two page letter, Einstein laid out the facts as they were then known. In short, he told FDR that it was possible to create large amounts of energy with certain radioactive elements, namely uranium. This energy could be released slowly, as is the case in modern nuclear reactors, or it could be released suddenly with great explosive force. It was the latter possibility that troubled the genius.

Einstein recommended that the federal government maintain closer contact with the researchers working on creating a sustainable chain reaction. He also recommended that the government provide funds to speed up the work that had, up to that point, only been conducted in university labs.

The letter ends with this ominous paragraph:

“I understand that Germany has actually stopped the sale of uranium
from the Czechoslovakian mines which she has taken over. That she should
have taken such early action might perhaps be understood on the ground
that the son of the German Under-Secretary of State, von Weizsäcker, is
attached to the Kaiser-Wilhelm-Institut in Berlin where some of the
American work on uranium is now being repeated.”

It is in this paragraph that Einstein explains his sense of urgency: the Nazis were working towards an atomic weapon, so the United States needed to put more coal on the research fire.

Einstein wrote three more letters to President Roosevelt, with the last one being received by the White House after the President’s death on April 12th, 1945. In it, he expressed concern that the scientists working on the Manhattan Project (Einstein was not one of them) did not have access to the policymakers in Washington. In short, he did not believe that the politicians in Washington had an appreciation of how nuclear weapons would change the world.

In his later years, Einstein referred to his first letter to FDR as the greatest mistake of his life. While he undoubtedly felt that he helped open the Pandora’s box of nuclear power, he can not be held accountable. The war-like nature of man would’ve stumbled into nuclear weapons even if Einstein had never been born.