In my understanding of WW2, it seems like the Nazis were on their way to winning. The United States was neutral in the war and wasnt hurting anyone. Then all of a sudden Japan bombed the US and gained an enemy which forced the US to go into the war and basically shift the weight so that the Axis would lose. I know that there were supporters of both sides in the US and that is why we weren't in the war in the first place.

I think an appropriate metaphor would be two guys are in a close fight but they're coming towards the end and one is on his way to winning. Then before the guy defeats his opponent, he attacks some third guy so it's 2 v 1 which makes him lose.

Was it hubris? A miscommunication between Japan and Germany? I don't doubt that its more complex than what I've explained but could somebody clear this up for me? I really don't see how attacking a powerful neutral party would benefit your side in a war. Any help appreciated.