I disagree. By denying Southerners the right to secede from a union of their own making they became slaves...demonstrating the hypocrisy of all those who desperately want the northern cause and their aggression to somehow be morally superior to the Southern cause. You simply cannot be simultaneously for and against slavery, even if one is bondage and the other is by denial of self governance...both eliminate self determination.
It’s the one fact Southernphobes and Lincoln lovers can neither refute nor acknowledge, because it destroys their world view and holier than thou self image. To admit the truth is to admit that they support the slave master and that they actually should loath themselves. Not going to happen.
That’s a lot of words to describe what the war was. That war was about making Washington, DC the central power of it all.