On Aug. 2, 1939, Albert Einstein wrote a letter to “F.D. Roosevelt, President of the United States,” outlining the potential of uranium to create a chain reaction and of Germany’s interest in this raw material. His letter was fundamentally about a new type of energy, and it began directly: Some recent work by E.Fermi and L. Szilard, which has been communicated to me in manuscript, leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. Certain aspects of the situation which has arisen seem to call for watchfulness and, if necessary, quick action on the part of the Administration. I believe therefore that it is my duty to bring to your attention the following facts and recommendations …Einstein’s letter is clear and short. In just over 500 words, he outlines the state of nuclear science and its then uncertain potential to build “extremely powerful bombs of a new type.”The letter closes with a piece of intelligence about what can be called the competitive threat posed by Germany.