Trump is not a threat to Democracy. Trump is not an autocrat. When Trump leaves office (whether by election or by death) American politics will be essentially the same as it would have been if Hillary or Cruz were elected instead: in the clutches of oligarchs and needlessly divisive due to a corrosive media environment made awful by 24 hour news networks and evil by the substitution of opinion and lies in place of news.
Trump has done little to make either of these things worse, and it is impossible that either would have changed since 2016 with a Republican held Senate.
Trump is far too vain and far too stupid to truly corrupt democracy. He’s certainly made some very, very small minded moves at self-enrichment (the Doral scandal most embarrassingly small-minded of all), but he is also far too easily swayed by public backlash and far, far more interested in being cheered at rallies than in actually using the levers of power for any dangerous purpose. He’s a clown, and an idiot, and his danger lies only in that a smarter corrupt fraudster or autocrat would have been far more successful in diminishing the power of Congress and corrupting the government as a whole.
Trump has not weakened Congress. The Senate could convict him and remove him and he would be powerless to stop it. There might be violence, but his most adamant supporters are gullible and small-minded in the image of their idol. The reason the Senate will not convict him is because he is weak, not because he is strong. Is it bad that such a weak fraudster is going to lead to the Senate debasing itself and setting a precedent for Presidential immunity from conviction? Sure, but that stage has already been set more strongly by the oligarchs’ intrusion into elections and by the media’s echo chambers than Trump himself.
Trump should be convicted and removed for violating the Constitution. The threats to American Democracy lie elsewhere, though. To credit Trump with anything of that gravity would be to confuse him for something other than the useful idiot he has proven to be.