Prior to World War One, it was thought that the machine gun was such an awful and powerful weapon that they would prevent war from happening, because no one in their right mind would want to go up against them. As that has long since proven to be wrong, do not doubt for a second that those who say that nuclear weapons will prevent war, or that no one would use them so the next war would only use conventional weapons are dead wrong. History has proven that this is the kind of thing that only fools believe.