File this under "Wow, I didn't know that!". Jack at Random Thoughts has a post about Dr. Seuss's political cartoons, with some great examples.
We have most of his children's books, including the Butter Battle Book, which, to an adults perception is pretty much a piece against nuclear war. But I had no idea that he wrote political cartoons during World War II, which unfortunately, could be published today with only minor alterations.
Worth a look.