Trump is not emperor for life, fortunately. He'll be gone in a couple of years. With any luck the upcoming midterms will significantly limit his powers. America will recover from this dark period. Other countries have had dark periods too, like Germany, and recovered.
Germany got a whole new constitution which was fairly explicitly designed to prevent that from happening again. The trouble for the US is that it is now very clear that the US president can just act like a crazy dictator, and that the mechanisms which were supposed to prevent that simply don't function. Absent constitutional change (which the US system makes virtually impossible), well, sure, there might be sensible…
This is true. A US president who has strong support from a majority of voters of his own party can act like a dictator. So if 51% of Republican voters (which may be just 25% of all voters) support him no matter what, then he can act like a dictator. This is because Republican members of Congress who are supposed to rein him in are worried that they will be voted out if they anger the 25% of voters who support the president.
The fact that 25% of voters can set the direction for the whole country is indeed a defect in the system that is not easily rectified.
But if Republicans are defeated by Democrats in the upcoming midterms then there is hope. That's how we are going to recover.