So am I correct that your objection isn’t to secession itself, which was Lincoln’s stated causus belli, but to slavery?
If that’s the case, then once again the Crown declared slaves emancipated during the Revolution. So do you then side with King George and emancipation? Or with the Americans and the continuation of slavery?
If your problem is secession itself, which was Lincoln’s position, how do you defend the Colonials seceding from Great Britain?
I’m saying that no Constitution is a suicide pact, so that within the confines of the United States Constitution, there is no “right” to secede.
But if you’re going to go outside of the Constitution and revolt, you better have a really good moral cause for your actions, because you’re going to have to justify it to God and the whole world.
If you can’t do that, and premise your rebellion on an unjust cause, you’re probably never going to gain access to the kind of physical means it’s going to take to carry out your revolutionary acts.