Anti-nuclear protests began on a small scale in the U.S. as early as 1946 in response to Operation Crossroads. Large scale anti-nuclear protests first emerged in the mid-1950s in Japan in the wake of the March 1954 Lucky Dragon Incident. August 1955 saw the first meeting of the World Conference against Atomic and Hydrogen Bombs, which had around 3,000 participants from Japan and other nations. Protests began in Britain in the late 1950s and early 1960s. In the United Kingdom, the first Aldermaston March, organised by the Campaign for Nuclear Disarmament, took place in 1958.