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
The Beast from 20,000 Fathoms in the Arctic Circle. The beast begins to wreak a path of destruction as it travels southward, eventually arriving at its ancient spawning grounds, which includes New York City. "The Beast from 20,000 Fathoms" was one of the first atomic monster movies which helped inspire a generation of creature features. Far north of the Arctic Circle, a nuclear bomb test, dubbed "Operation Experiment", is conducted. Prophetically, right after the blast, physicist Thomas Nesbitt muses, "What the cumulative effects of all these atomic explosions and tests will be, only time will tell". The explosion awakens a long carnivorous dinosaur known as