You're leaving out the part about those folks in the states who wanted to join the union in the first place. Don't they have anything to say about it?
First, the people of a state had to "want" to be a part of the union, and secondly the people of the union had to "want" the people of the state to be in their union. In each case the results were something both people "wanted".
What we saw in the Confederacy was the people of the southern states saying "we don't want this any more"...so they left. It was their right to do that, just as much as it was their right to join the union in the first place. As to why they wanted to leave is irrelevant.
The one thing that stands out about the Framers was their emphasis on the rights of the people of a state over the rights of any central government. Did the people of early America ask King George's permission to leave the empire?
What Lincoln did was to say to the people of the Confederacy "Oh, no you don't. You have no right to leave something you joined." This is the same mentality the Soviets had when they sent troops into Balkan countries that tried to leave the Soviet Union. The only difference being those countries never voluntarily joined anything. But, the rallying cry was the same: "We must save the union".
World history is replete with peoples who "wanted out", but were forced back at bayonet point. The Framers knew that, and gave us a document that allowed states the right to shed a central government if they disliked it without having to ask permission. That's what freedom is all about. If you have to ask to leave...you aren't free.
" The Framers knew that, and gave us a document that allowed states the right to shed a central government if they disliked it without having to ask permission."
I thought it was hilarious, during the 2000 election recount fiasco, that Albert Gore (of all people) suddenly turned pro states rights. Any port in a storm, I guess. LOL.
Just because the people of a territory might "want" to become a state, they don't become one until a majority of the states agree to admit them, through a vote in Congress. So if the people of a state "want" to leave the Union there should be no reason why the other states would not "want" to let them leave if that state asked. But that second step was never taken. The southern states acted unilaterally and chose rebellion as their path.
It was their right to do that, just as much as it was their right to join the union in the first place.
I've read the Constitution end to end and I'm not aware of any "right" to join the Union. States are admitted, only with the permission of the other states. They can wait for years for that permission to occur. They have no more right to unilaterally leave the Union as they have to unilaterally join it.
Did the people of early America ask King George's permission to leave the empire?
Nope. And they didn't pretend that their actions were legal, either. They realized that they were entering into a rebellion and were aware that they would have to fight for their independence. The southern states, by comparison, chose rebellion and were outraged that their actions were opposed. And they also lost their rebellion. That's another big difference.