[lentulusgracchus]

To say that when the individual states gave up their sovereignty that they ceased to be a people is doing it too brown to put it mildly.

Well, let's proceed on this line a little further. I've told you what I think........what then, did the States give up at the moment of ratification? Do you subscribe to Lincoln's "Suitors of Penelope" construction: that once they ratified, the doors slammed shut and were bolted behind them, and the Many Unintended Entrained Consequences set in motion? Do you think Rhode Island's reservations were valid, or is there language in Article VI, Article VII, or George Washington's covering letter, that precludes Rhode Island's taking a reservation?

Do you think the States bound themselves thereafter helplessly to the United States Government, regardless of what they had intended, under the theory that They Should Have Known? That the People's assent to government is not "perpetual", i.e. continually given, but that it is a one-time, instant decision on the threshold, that binds them forever and forever to the discretion of United States magistrates and the Chief Executive?

Is the United States Government the Sovereign of the U.S.A., its Lord, Master, and God Emperor? Well?

[Frumious Bandersnatch]

The way the constitution is written, sovereignty is vested in the constitution.  Each state is prohibited from making treaties, wars, regulating interstate commerce, etc.  The supremacy clause indicates that the constitution trumps state laws.  As such, it is clear that no state can secede since they are not allowed many of the functions of a sovereign state.  And without these functions, they cannot be said to be sovereign.