We’re putting the cart before the horse. Why do you think states have the right to secede? Nowhere in the constitution does it give them the right. Something as serious as dissolving the union would have something explicit written wouldn’t you think?
We seceded from England, didn’t we, “ after a long train of abuses”?
We used to be the United States. Now we’re USA. I don’t know if the Constitution says anything, one way or the other. Certainly the South thought it had the right to secede.
Show me the article/section prohibiting secession. The USC would not have been ratified if their was a "roach motel" clause - states go in the union but can't get out.