But not to secede without the agreement of the other states. The Supreme Court ruled that in 1869.
SCOTUS was a joke then and it's a joke now.
South Carolina had 10 other states agree with their secession.....
The agreement of other states is no more required than the agreement of the other kingdoms of the British Union. We didn't need approval from Wales, Scotland, Ireland or England to exercise the right of self determination.
The Supreme Court ruled that in 1869.
The Supreme Court made that crap up because they were kowtowing to the political winds of the time. If you don't grasp how that works, I will point out Roberts, Kavanaugh and Coney Barret as examples of how that works in our current era.
The vast majority of actual real evidence demonstrates that a Union joined voluntarily could be left voluntarily.
To my knowledge, all you have to the contrary are two letters from Madison, and one of those written 40 years after the fact, and directly contradicted by the actual ratification statement of Virginia, and of which he was part of the group who wrote it.