LOL. States' rights is just what you describe, as anyone with even a rudimentary understanding of history knows. The South seceded because their leaders wanted out. They had wanted out for a long time. Some of them never really wanted in. They never liked the Constitution. Patrick Henry was a typical slaver. He acknowledged early on that the Constituion spelled doom for slavery. He professed to hate slavery, but he practiced it, and thought it "imprudent" that it ever--ever--be abolished. It was men like him who seized whatever excuse was handy to try and destroy our government.
That is why the war was not strictly about slavery. It was just another incorporation of a region of the country into the Federalized Union. Sort of a rock rolling down a hill...the momentum carried the day....and the foolishness of many.