Which is why Texas vs. White, the cobbled-up Supreme Court decision the opinion in which was written and handed down by a Chief Justice who spent most of the Civil War as an active combatant in Lincoln's cabinet, was totally unconstitutional -- among other things, Chief Justice Chase found that the Confederate secession conventions were all, all illegal, that the People of the States had no power to withdraw from having the Union enforced on them.
Which is an imbecilic finding considering that the current US Constitution was formed AFTER States began seceding from a document called the Articles of Confederation and Perpetual Union.
If they could do it then, they can certainly do so in a compact where any such permanency is never even hinted at.