After the war, the future of the Laboratory was uncertain. Hundreds of scientists and technicians left Los Alamos in fall 1945. In fact, by spring 1946 the Laboratory employed only 1200 staff members; approximately half its wartime complement. Many of the tenured staff members returned to academic posts, while younger workers left to complete advanced degrees. Even J. Robert Oppenheimer, the Laboratory's brilliant wartime leader, resigned just weeks after the conclusion of the war.
Defining the Role of the Postwar Laboratory
During this time, the Laboratory lacked a clear mission. Politicians and scientists struggled to define the role of atomic energy in the months following Hiroshima and Nagasaki. The army had managed the nation's atomic bomb project during the war, but it would soon cede control to a civilian agency. However, it would take congress months to enact the legislation creating the agency, leaving the Laboratory in limbo. Such was the state of the Laboratory when Norris Bradbury officially became its second Director on October 17, 1945.
In the months following the war, negotiators failed to strike an international deal to outlaw the further development and stockpiling of nuclear weapons. Meanwhile, Bradbury gradually began rebuilding the Laboratory. He increased efficiency, reorganized the Laboratory to operate on a peacetime civilian basis, and directed the staff to continue work on weapons development.
From Expendable Outpost to National Asset
Gradually, Bradbury rebuilt the Laboratory and worked closely with the army and its civilian successor, the Atomic Energy Commission, to solidify the institution's future. By the late 1940s, funding was secured to rebuild the main technical area and improve housing, as the Laboratory refined and tested fission weapons and gradually expanded the hydrogen bomb research program. Two test series, Operations CROSSROADS and SANDSTONE, were conducted in 1946 and 1948, respectively. Six nuclear weapons tests were conducted in the 1940s, allowing the nation's stockpile to grow from two bombs, in late 1945, to 170 in 1949. Under Bradbury's direction, the Laboratory was transformed from an expendable wartime outpost into an institution at the heart of early Cold War national security.