Anyone who's read the transcript of Trumps telephone call to Mexican President Enrique Peña Nieto an/or his call to Australian Prime Minister Malcolm Turnbull clearly knows how very insane Trump is. They certainly do.
( Please read, if you haven't: https://www.washingtonpost.com/graphics/2017/politics/australia-mexico-transcripts )
He'll serve his first term, but the party will back another, younger candidate to run against him, while at least one faction of his supporters will ride the dying horse to his death.
Barring his death, or some severe mental disability, he won't be replaced. The party needs to demonstrate their 'unity' (Ha!) to keep the viewers of the West Wing reality show engaged. They don't want anyone to know the General's really the one in charge.
We need only pay attention to the legislation & executive orders Trump signs and the damage being done in the agencies headed by his cabinet cronies. And we need to pay attention to the Generals. Trump is the clown we're not supposed to take our eyes off while the real magic occurs unnoticed.
Regardless of party, and the persona of whoever's occupying the Oval Office, the game will continue, with slight adjustments along the way, just as it has forever.