If they can beat big, bad brother, then they win.
Look, I don't think this is anything we're going to solve on VolNation. It's a very complex question.
I just think that, typically, strong nations keep one another in check. Small, divided ones stand the risk of getting ran over. Of course this doesn't always prove the case in reality.
The US kept the USSR in check? How so?
Did the USSR keep the US in check? Again, how so?
Oh, wait, when the three most powerful nations in the world were Britain, France, and Germany, they kept each other in check, right? Except for all those pesky little wars and that whole debacle called colonization...