Uh, the Civil War started because of States leaving the Union, not slavery. Granted, slavery was a large part of it. The Confederate Flag has everything to do with State's rights and very little (if at all, but there are always THOSE guys who ruin it for the majority) with slavery.
Again, I can always refer people to books if asked. I can't be bothered to source 40-45 great reads on the topic, including many contemporary sources (just for you, rumborak). But, if I have to, please ask.