Or did the eleven states that attempted to leave do so out of a conviction that their "states rights" were being trampled by the federal government?
A popular argument sprang up across the South after the war ended in 1865 that fostered and supported the latter. That it was all about "states rights." Most historians today go with the former. That slavery was the issue.
I'm reminded of that ongoing debate by an op/ed in today's New York Times, written by Edward Ball:
Gone With the MythsHere's the deal: Is Mr. Ball right? Was the prime mover that brought on secession the institution of slavery? Without doubt. But did Southern politicians in those tumultuous years justify their blocking national legislation (pertaining to slavery in particular, but on other issues as well; see "Tariff of Abominations" as a good example) and ultimately leaving the Union by citing states rights? Without doubt.
I can testify about the South under oath. I was born and raised there, and 12 men in my family fought for the Confederacy; two of them were killed. And since I was a boy, the answer I’ve heard to this question, from Virginia to Louisiana (from whites, never from blacks), is this: “The War Between the States was about states’ rights. It was not about slavery.”
I’ve heard it from women and from men, from sober people and from people liquored up on anti-Washington talk. The North wouldn’t let us govern ourselves, they say, and Congress laid on tariffs that hurt the South. So we rebelled. Secession and the Civil War, in other words, were about small government, limited federal powers and states’ rights.
But a look through the declaration of causes written by South Carolina and four of the 10 states that followed it out of the Union — which, taken together, paint a kind of self-portrait of the Confederacy — reveals a different story.
[W]e will likely hear more from folks who cling to the whitewash explanation for secession and the Civil War. But you have only to look at the honest words of the secessionists to see why all those men put on uniforms. [link]
In fact, both sides are right. Slavery was the underlying issue that drove the South to (attempt to) go its own way. "States rights" was the mechanism that was used to support the effort. The fuse, the dynamite, and the match.
It's not an "either/or." It's both.