1958 US–UK Mutual Defence Agreement as an atomic spy, caused the proposal to be dropped. The June 1951 defection of Donald Maclean, who had served as a British member of the Combined Policy Committee from January 1947 to August 1948, reinforced the Americans' distrust of British security arrangements. The first British atomic bomb was successfully tested in Operation Hurricane on 3 October 1952, but although it was more advanced than the American bombs of 1946, Britain was still several years behind in nuclear weapons technology. The United States conducted Ivy Mike, the first nuclear test of a true thermonuclear device (also known as a hydrogen
Nuclear weapons tests in Australia atomic tests at Emu Field in 1953 were known as Operation Totem The atomic tests at Maralinga in 1957 were known as Operation Antler A testing site at Maralinga was established in 1955, close to a siding along the Trans-Australian Railway. Because supplies could be brought to the site via rail, it was preferred over Emu Field. A total of seven major tests were conducted at Maralinga. Both the Federal government and Australian newspapers at the time were very supportive of the tests. In 1952, the Liberal Government passed legislation, the "Defence (Special Undertakings) Act 1952", which allowed the British