Not going along with the adminstration's policies is one thing. Letting corrupt Republican politicians off the hook is another.

Under Clinton in one case in NJ, nearly the entire Democratic machine of Hudson County was indicted with the main players going off to jail. And, these were big supporters of Clinton. Those USA's didn't get "the can".

EDIT:

That's politics. But, he didn't fire ALL of them. I know a USA in KY whose a staunch Christian Republican who kept his job. But, those firing happened at the beginning of his administration after 12 years of Republican political appointments. Not those whose performance was rated highly by the "firing" administration just prior to their being dropped.