The Manhattan Project, a secret federal project to develop an atomic bomb, begun in 1939, had, by the end of the war, employed 130,000 staff, and cost $2 billion. The National Defense Research Committee (NDRC), established by FDR in 1940, was headed by Vannevar Bush, the so-called czar of research, who by 1941 was also head of the Office of Scientific Research and Development. Before the end of the war, the NDRC employed some two thousand scientists, including three out of four of the nation’s physicists.
