He probably means the civil war.

I'd like to point out that the South was only a fan of States Rights exactly insofar as they let them do slavery. The millisecond it came to forcing Northern states to return escaped slaves, they suddenly weren't the same principled supporters of devolving and federating power. Funny how that works.

And just in case it wasn't clear enough already: one of the first acts of the Confederacy was to draft a provisional constitution which explicitly authorized slavery, and which prohibited either Congress or any state from passing laws to the contrary.

Yeah, I just wanted them to cut out the coy vagueposting and say out loud how bad they think Reconstruction was.

So in that respect, mission accomplished.