Albert Einstein writes President Franklin D. Roosevelt, alerting the President to the importance of research on nuclear chain reactions and the possibility that research might lead to developing powerful bombs. Einstein notes that Germany has stopped the sale of uranium and German physicists are engaged in uranium research.
President Roosevelt approves production of the atomic bomb following receipt of a National Academy of Sciences report determining that a bomb is feasible.
President Roosevelt instructs the Army to take responsibility for construction of atomic weapons complex. The Army delegates the task to the Corps of Engineers, which establishes the Manhattan Engineer District.