What was the biggest mistake Japan made in WWII?

The japanese emperor was quoted soon after the pearl harbor attack as saying " I fear we may have woken a sleeping giant". At least I think it was the emperor, may have been one of the top military brass. The big mistake they made however, was in getting together with the germans on the plan to drop several nuclear weapons on the west coast of the U.S. This solidified the U.S. decision to drop the bombs on Nagasaki and Hiroshima.

LOL, another good one. even they said, where they messed up was attacking the U.S.A. It's good for us that they did. we didn't get into the war until they attacked us. if we had stayed out of it, after everyone else was defeated, they would have all attacked us. then we would all have been ruled by germany. not good. I like my freedom.

they invade philippines...