Again, it would help for you to post the part of the US Constitution that specifically prohibits state secession. Thanks in advance. I will wait. TTYL
We’re arguing at cross purposes. You are assuming the Constitution of 1789 changed the terms of perpetual union specified in the Articles. I am saying that because the new Constitution did not address those terms, the old terms remain in effect, unless a state joined with a qualification such as Texas. And the issue with Texas is whether the current state of Texas is the legal successor to the original.