“Sadly, only those who are appointed can be fired.”
The State Department was infiltrated in the 30’s and 40’s by socialists. That’s the reason we find the State Department’s actions continually undermine the interest of the US.
Hell!! Transfer them to an empty federal building in Oklahoma or Missouri and sit them at an empty desk with no work to be performed. That will at least minimize their potential for damage and get them the hell out of DC.
If they don't like it they always have the option to quit.