nMay 9
nThe Interim Committee meets for the first time.  Its purpose is “to study and report on the whole problem of temporary war controls and later publicity, and to survey and make recommendations on post war research, development and controls, as well as legislation necessary to effectuate them.”  The Interim Committee appoints a Scientific Panel, which included Oppenheimer, Lawrence, Fermi and Compton.
nMay 25
nLeo Szilard visits White House with letter of introduction from Albert Einstein to warn President Truman of the dangers atomic weapons pose for the post-War world and to urge him not to authorize use of atomic weapons against Japan.  Szilard is referred Matthew J. Connelly, Truman’s appointments secretary, to James Byrnes in Spartanburg, South Carolina.