The Manhattan Project: Making the Atomic Bomb
The Department of Energy Organization Act of 1977 brought together for the first time in one
department most of the Federal Government's energy programs. With these programs came a score of
organizational entities, each with its own history and traditions, from a dozen departments and
independent agencies. The History Division has prepared a series of monographs on The Origins of the
Department of Energy. Each explains the history, goals, and achievements of a predecessor agency or
a major program of the Department of Energy.
"The Manhattan Project: Making the Atomic Bomb" is a short history of the origins and development of
the American atomic bomb program during World War II. Beginning with the scientific developments
of the pre-war years, the monograph details the role of United States government in conducting a
secret, nationwide enterprise that took science from the laboratory and into combat with an entirely
new type of weapon,The monograph concludes with a discussion of the immediate postwar period, the
debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.
The author wishes to thank Richard G. Hewlett, Jack M. Hell, and Thomas Comwell for reviewing the
manuscript and making numerous valuable suggestions. He also wishes to thank Glenn Seaborg for a
thorough critique that improved the final product. Others who read and commented on the manuscript
include Roger Anders, Terry Fehner, Alice Buck, Betsy Scroger, and Sheila Convis. Finally, the author
thanks La Shonda Steward for research support, Betsy Scroger for a first-class editing job, and Sheila
Convis for project support.
The Einstein Letter
On October 11, 1939, Alexander Sachs, Wall Street economist and longtime friend and unofficial
advisor to President Franklin Delano Roosevelt, met with the President to discuss a letter written by
Albert Einstein the previous August. Einstein had written to inform Roosevelt that recent research on
chain reactions utilizing uranium made it probable that large amounts of power could be produced by
a chain reaction and that, by harnessing this power, the construction of "extremely powerful bombs..."
1 was conceivable. Einstein believed the German government was actively supporting research in this
area and urged the United States government to do likewise. Sachs read from a cover letter he had
prepared and briefed Roosevelt on the main points contained in Einstein's letter. Initially the President
was noncommittal and expressed concern over locating the necessary funds, but at a second meeting
over breakfast the next morning Roosevelt became convinced of the value of exploring atomic energy.
Einstein drafted his famous letter with the help of the Hungarian émigré physicist Leo Szilard, one of a
number of European scientists who had fled to the United States in the 1930s to escape Nazi and
Fascist repression. Szilard was among the most vocal of those advocating a program to develop
bombs based on recent findings in nuclear physics and chemistry.
Those like Szilard and fellow
Hungarian refugee physicists Edward Teller and Eugene Wigner regarded it as their responsibility to
alert Americans to the possibility that German scientists might win the race to build an atomic bomb
and to warn that Hitler would be more than willing to resort to such a weapon. But Roosevelt,
preoccupied with events in Europe, took over two months to meet with Sachs after receiving Einstein's
letter. Szilard and his colleagues interpreted Roosevelt's inaction as unwelcome evidence that the
President did not take the threat of nuclear warfare seriously.