“If they move against the 2A, then they are breaking the contract, and it’s no longer valid”
Exactly. The “union” is not some magical mystical beast. It is simply an agreement. If they ignore the agreement then we get to ignore it, too.
And the 2A is the line in the sand.
Ask the Armenians, Russians, and the Jews:
Did the Turks, Soviets and Nazis treat them better, or worse, after they were disarmed in the name of “public safety?”
No gun control regulation is likely to pass the House. The rest is fantasy.