robert oppenheimer: we knew the world would not be the same. man: we saw this cloud of boiling dust and debris below us with its tremendous mushroom on top. beneath that was hidden the ruins of the city of hiroshima. kermit beahan: when the clouds opened up over the target of nagasaki, i let the bomb go. different man: if the announcement made by president truman that the soviet union now has the atomic bomb is true, then the impasse that now exists regarding the international control of atomic energy must be brokered for the sake of mankind and for the peace of the world. newsreel narrator: just-released film show the recent a-bomb tests in which britain joined america and russia as the third world power to possess atomic weapons. man: this first blast is on a level with bombs exploded over hiroshima and nagasaki in world war ii. now france presses forward to force her way into the exclusive nuclear club. john f. kennedy: this government has maintained the closest surveillance of the soviet military build-up on the island of cuba. the purpose