History of the United States 6–3 decision in Korematsu v. United States Supreme Court case. Research and development took flight as well, best seen in the Manhattan Project, a secret effort to harness nuclear fission to produce highly destructive atomic bombs. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the U.S. Army Corps of Engineers. Nuclear physicist J. Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the actual bombs. The first nuclear device ever detonated was an implosion-type bomb at the Trinity test, conducted at New Mexico's Alamogordo Bombing and Gunnery Range on
Nuclear weapons and the United Kingdom weapons to be a joint discovery, but the American Atomic Energy Act of 1946 (McMahon Act) restricted other countries, including the UK, from access to information about nuclear weapons. Fearing the loss of Britain's great power status, the UK resumed its own project, now codenamed High Explosive Research. On 3 October 1952, it detonated an atomic bomb in the Monte Bello Islands of Western Australia in Operation Hurricane. Eleven more British nuclear weapons tests in Australia were carried out over the following decade, including seven British nuclear tests at Maralinga in 1956 and 1957. The British hydrogen bomb programme demonstrated