[Non-Sequitur]

Quote the part of it that forbids secession. I'm genuinely interested. It's not in any part of it that I can find.

Not in any part I can find, either. Nor can I find anything in the Constitution which allows secession without the consent of states. Perhaps you can point that part out?

[FreedomCalls]

Nor can I find anything in the Constitution which allows secession without the consent of states. Perhaps you can point that part out?

Sure, no problem. It's right there in the Tenth Amendment:

Amendment 10

The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.

Unless you can point out where the power of approving secession was delegated to the United States or prohibited to the states, then it is a power they retain individually.