He'll cut off all government financing, shut down bank transactions and ATM, the internet and cause all sorts of chaos before that becomes necessary.
If the battle is at the state level, the Fed will go to war as a warning to others. Texas is the biggest kid on the block and they will try to kneecap them early in the game as a warning and example to others.
The states collect federal taxes and send them to the feds. Texas should continue to collect the federal taxes, but not send it to the feds, but instead use it to do what the feds are refusing to do - shut off the flow of illegals into the state. Yeah, the feds can sue. We can tell them to go pound sand!
He might get more than he bargained for in Texas. Or any other God fearing, Gun Loving state. Especially one that is home to lots and lots of vets. I’m in LE and I know quite a few that will have no problem refusing orders if they ever come.
He might just end up getting on one of Soro’s jets and being run out of town if he pushes it that far.