O.k. I'll weigh in.
What most people forget is that besides foreign policy, veto power, and court nominations the President doesn't really have that much power - it's a bug/feature the "founding fathers" instituted to avoid monarchs.
The power the President does have is to guide the political conversation and shape it using the office basically as a pulpit. The press and the people closely follow (or at least used to) what the President shines a spotlight on, and how he/she does so, that's the power of the office.
Trump has used the office to up end every possible role, protocol, or accepted behavior that came before him. In doing so he's gained a cult like status of those who want to "shake things up" or "change the system" even while Trump et al. are passing bills that directly work against their self interest.
The Democrats vs Republicans has become the modern day version of the Hatfields vs the Mccoys or Montague vs Capulets - at least for one side. Those who are actually engaged can probably agree that most of the things Trump has done while in office hurts almost everyone - yet his diehard supporters love it because their team is winning.
Basically I think Trump is sort of like the Joker - a character who sows chaos for self aggrandizement and someone who "just wants to watch the world burn".
But...and there is a but...while doing so he's enacting the basic right wing policies that have been around for 50 years while everyone distractedly stares in horror saying, "He did/said what?"
Sorry for the pop reference, but I think it's pretty apt.
Donald Trump is the ultimate three cars monte player.
His ability to masterfully hide the Queen, keeps both political parties, the Country,
and all us citizens guessing and off balance.
To date his strategy has been "successful"
For me the question has never been about Trump's cognitive ability.
I have been and am more concerned about a personality disorder.
I believe he is a pathological narcissist. "I'm a stable genius", "I'm the least racist person you have ever interviewed" etc.
The litany of statements supporting my view is too long to list.
I am not a Clinical Psychologist, but I know a good one who is part of headcycle.
I am interested in his opinion, and/or anyone else's.
I am not a fan of armchair diagnosis, (mine), or diagnosis without professional examination,
and I hope that I am wrong, but to quote The FlyII " Be Afraid , Be Very Afraid".