"Bugs Bunny Nips the Nips" is one of the many cartoons that you would have to watch not as straight-forward entertainment, but rather so as to see the sorts of stereotypes that pervaded during WWII. In this case, the world's most famous rabbit washes up on a Pacific island and has to battle a whole slew of stereotyped Japanese people (and at one point even goes so far as to use the derogatory term for a Japanese person). He goes to some rather ugly extremes.
Yes, it's totally racist, but definitely worth seeing as a reference. I wonder whether or not the Axis governments commissioned propaganda movies portraying Americans as ignoramuses; I know that the Japanese government showed its troops Abbott & Costello movies and claimed that all Americans were like that.