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
Las Vegas in the 1950s tests began at the Nevada Test Site, north of Las Vegas ( from downtown Las Vegas) on 27 January 1951. After it was shown on television on 22 April 1952, the Las Vegas town and the nation was gripped by the atomic fever and the Chamber of Commerce even brought out a calendar showing the vantage points to view the atomic sites. Atomic Cocktails, Atomic hair-dos, and Miss Atomic Blast beauty contests became popular with people in some of the casinos. Testing continued until the 1963 Test Ban Treaty came into effect and surface testing was banned and underground testing