“They also know that President Trump can invoke the Insurrection Act to fight them, and use the military.”
This could present a problem as many of the high ranking officers are questionable as we have seen recently. Upon reelection Trump must clean the ranks of Obama officers.
If the President of the United States invoked the lawful Insurrection Act against domestic enemies, and officers or enlisted military refused that order, they themselves would be subject to the most severe punishments under the UCMJ. Not only would they be violating their oaths upon enlistment and commission (the oaths are very similar, with slight differences for officers and enlisted), but they would be in violation of several statues of the UCMJ.