What rules exactly did the North “violate”? Lincoln wasn’t even sworn in yet when the southern states started to succeed. They made it clear that they would if he won even before the election.
As for the much vaunted southern love of states rights, ever heard of Dred Scott? They had no concern for the rights of free states not to have to participate in a system of slavery they considered immoral when they made them treat escaped slaves as property to be returned. And in doing so they made ending slavery a moral issue for the north.
Yes, I have heard of Dred Scott.
Most of the rest of the world managed to abolish slavery without war. Lincoln was a tyrant.
By most reasonable accounts, a right of the states. But to "statists" MIGHT MAKES RIGHT. Lincoln had might, so the civil war is viewed as a moral wrong.