This one was during an interview with Salena Zito for The Washington Examiner, a conservative magazine/website. They were talking Andrew Jackson, he brought up the U.S. Civil War in a way that made you wonder if he didn't realize Jackson wasn't alive during the U.S. Civil War, and then he added this: 

People don't realize, you know, the Civil War, if you think about it, why? People don't ask that question, but why was there the Civil War? Why could that one not have been worked out?

I don't know if he's trying to appeal to the usual racist cons, who claim secession wasn't due to their wanting to own human beings, or if he's just a massive dipshit, or both.