Doubtful it ever will. A major war, perhaps. A world war, doubt it. With the United Nations set up the way that it is, I doubt we'll ever see a war in which all the powers collaborate together. What's the point of war anymore? In the past, it was a matter of who could defeat each other, who had the bigger army, etc...With today's nuclear weapons, it's anybody's game. We could all wipe each other out, so war has nearly become a mute point.