I don’t think they believe in the whole separation of powers thing.

Right now, if Trump's approval numbers go down, especially with the base, it's not something that he can't recover from, therefore, it's safe for Hannity to drive those numbers down. Later, he can say, "Mr. President, the last time you compromised with the Democrats, you lost X points in polling, and most of that came from your base. You can't afford that this close to the election."

Trump is easily manipulated, just ask Putin. You can bet that Hannity and Coulter have figured out how to use that to their advantage.

he is just playing to his deplorable audience.

is that Hannity is smarter than Trump. It's like calling Moe the "smartest" of the Three Stooges.