OK take out the Hollywood stuff (gunbattle) and look at the factions...
Do the people being jettisoned from administration posts fit into a faction?
I wouldn’t put much past this regime. But this is getting a little far fetched given the fact that the Left will be able to effect a coup through regulatory changes, replacements on the Supreme Court, a weak and spineless Congress and a confederate press corps. They have no need for such heavy handed tactics as pulling a general out of his car at gunpoint. But like you say, gunplay aside, are the factions probable? Sure.