The United States Atomic Energy Commission (AEC) was an agency of the
United States government established after World War ll by Congress for the
peace time development and control of atomic science and technology. It began
when President Harry S.Truman signed the McMahon/Atomic Energy Act (above)
on August 1, 1946, transferring control of atomic energy from military to civilian
control, to be effective on January 1, 1947. President Truman appointed David
Lilienthal (below) as the first Chairman of the AEC. The AEC was reassigned into
two new agencies in 1974, the Energy Research and Development Administration
and the Nuclear Regulatory Commission. 

David E. Lilienthal