The first Atom bomb was detonated over Alamogordo, New Mexico on July 16, 1945. The physicist who assembled the nuclear core for this bomb was a physicist from Winnipeg, Louis Slotin. During the assembly he asked that Robert Oppenheimer, the father of the A Bomb, be ejected from the room because Oppenheimer was making Slotin nervous. Three countries were involved in the Manhatten Project: the US, the UK and Canada. Contrary to what most people think, it was Harry S Truman who decided that Canada and the UK be shut out from obtaining nuclear weapons. The UK went ahead and developed their own bomb with the help of the traitor, Klaus Fuchs. Canada decided to refrain from obtaining these weapons, and thus began the smug Canadian attitude that we were morally superior to the Americans.