Hey, I saw this movie! Thought it looked familiar.
What exactly is your point? It is not related at all to the OP. I simply don't understand why someone has to rush in and post "oh yeah, but the US did this!!" whenever anyone posts something about any other country doing something. The US was not warned of a specific attack on Pearl Harbor. They knew of the possibility of an attack by Japan. So:
1. They didn't know of a specific Pearl Harbor attack.
2. The declaration of war by Japan did not reach the US government until after the attack.
Which explains why it was a bit of a surprise. Especially back then, you expected war to be declared before an offensive is launched. If the US ended up attacking Japan based on the information they had, these same conspiracy theorists would be condemning the US for an unprovoked attack. Damned if you do, damned if you don't.