Which will also affect travel at the smaller feeder airports.

Chaos for the purpose of cover up. Who the hell cares who gets hurt? Protect the pedophiles at all costs. The new Republican Party Motto.

until the administration decides to pay them, I think this is necessary

NONE of this is necessary!
Not the ICE thuggery
Not the federal layoffs
Not the destruction of the norms
Not the fear mongering
Not the (you name it)

I've been wondering how and when they would try to shut down travel.

SLC, Houston, DFW, ORL, MIA, Ft. Lauderdale, PHX, Anchorage, Tampa, MEM, Charlotte, Louisville, Indianapolis? The city of Atlanta is blue-ish, but ATL (which is actually mostly in the suburbs of College Park and Hapeville) is one of the busiest airports in the US and is Delta's primary hub. Only MSP, BOS, the New York area airports, Portland, SEA-TAC, DEN, DTW and ORD are in blue states.

the way out there. I hope it's better coming back, but I kind of doubt it.

That's just what you want, the person talking your plane down fresh off of a 10 hour Amazon warehouse shift.