You just glossed right over that Declaration of Independence thing, didn't you?
If the right to independence given us by "nature, and Nature's God" can break the thousand year old English Union, it can certainly break one that was only "four score and seven years" old.
The principle articulated in the Declaration is the moral and legal crowbar to break any compact. It is the natural law right to independence granted by God, and no laws made by man can trump it.
DiogenesLamp: "You just glossed right over that Declaration of Independence thing, didn't you? "
No, because regardless of how much DiogenesLamp pretends otherwise: neither the Declaration of Independence nor any Founder ever declared an unlimited "right to secede" at pleasure.
Founders agreed to "disunion" or "secession" under two, but only two, conditions: