Nuclear fission Mexico, which was the scientific hub for research on bomb development and design. Other sites, notably the Berkeley Radiation Laboratory and the Metallurgical Laboratory at the University of Chicago, played important contributing roles. Overall scientific direction of the project was managed by the physicist J. Robert Oppenheimer. In July 1945, the first atomic explosive device, dubbed "Trinity", was detonated in the New Mexico desert. It was fueled by plutonium created at Hanford. In August 1945, two more atomic devices – "Little Boy", a uranium-235 bomb, and "Fat Man", a plutonium bomb – were used against the Japanese cities of Hiroshima
1947–50 in the Vietnam War and foreign affairs. The Accord was denounced by Ho Chi Minh and generated little support in Vietnam. Bảo Đại returned to Vietnam as Head of State after the agreement was formally approved by the French parliament. At a Department of State conference, Consul General George M. Abbott said that the only alternatives to a Bảo Đại government were a colonial war or a communist-dominated government of Vietnam. The Soviet Union detonated a nuclear bomb at a test site, breaking the United States' monopoly on nuclear weapons. The Soviet nuclear test amplified fears by the U.S. and its allies that the