Refusal to perform assigned duties*work) is cause for termination. This is even for Civil Service workers. Start firing them all.
How? There's no procedure for congress to fire anyone in the executive branch. And so long as they have the highest ranks in the department on board, no one within the agency will fire them either.
Obama's years in the White House certainly show us exactly what happens when you don't have any adults, anywhere, running the show. 'Oh, yeah, someone go, you know, do that thing with the flag, forgot about that. Alright, someone make sure that golf cart one is on standby, I think I've earned a good round of golf today!'