Operation Grapple Burgess and Donald Maclean in 1951. Fearing a resurgence of American isolationism and Britain losing its great power status, the British government restarted its own development effort, now codenamed High Explosive Research. The successful test of an atomic bomb in Operation Hurricane in October 1952 represented an extraordinary scientific and technological achievement. Britain became the world's third nuclear power, reaffirming the country's status as a great power, but hopes that the United States would be sufficiently impressed to restore the Special Relationship were soon dashed. In November 1952, the United States conducted Ivy Mike, the first successful test of a
Operation Upshot–Knothole the Simon test) was employed as primary for the ZOMBIE, RAMROD and MORGENSTERN devices. Operation Upshot–Knothole Operation Upshot–Knothole was a series of eleven nuclear test shots conducted in 1953 at the Nevada Test Site. It followed "Operation Ivy" and preceded "Operation Castle". Over 21,000 soldiers took part in the ground exercise Desert Rock V in conjunction with the "Grable" shot. "Grable" was a 280mm shell fired from the "Atomic Cannon" and was viewed by a number of high-ranking military officials. The test series was notable as containing the first time an atomic artillery shell was fired (shot "Grable"), the first