Lawrence Wittner, a historian of the post-war peace movement, argues that the Soviet Union devoted great efforts to the promotion of the WPC in the early post-war years because it feared an American attack and American superiority of arms at a time when the USA possessed the atom bomb but the Soviet Union had not yet developed it. This was in opposition to the theory that America had no plans to attack anyone, and the purpose of the WPC was to disarm the US and the NATO alliance for a future Soviet attack.