Of all the alarming things about President Trump (and there are almost too many to count), his ongoing compulsion to hold and encourage rallies in his own honor--even after he won the election and as though he were still campaigning--is probably among the scariest.
There's historical precedent for this of course, in Nazi Germany and in other fascist autocratic governments. Fortunately, Trump doesn't seem nearly as canny or effective as any of those figures, Hitler included. But the need to get high off your own supply of narcissism comes from the same combustible mix of fragile ego and a massive amount of power. Power that deep down, the man who has it knows he has not earned, cannot control, and is therefore always on the brink of losing.
So what does he do?
He surrounds himself and encourages the assembly of people who make him feel loved. People who tell him he deserves the job he doesn't want and knows he should never have gotten in the first place. It's the only thing that makes him feel good and that gets his serotonin receptors firing on full blast. He over-compensates for his total incompetence by generating faux public adulation and fanfare that serves no purpose other than to stoke his own ego.
What is the cost of this?
Well, the cost is actual governing or any attempt to unite the country under some semblance of leadership, which of course Trump is incapable of even if he weren't busy holding and encouraging rallies for himself in the middle of his presidency.
At the risk of armchair psychoanalysis or covering ground that has been covered ad nauseum, I don't think any of this is intentional. Trump is not insightful or self-aware enough to do this on purpose. It's not like he's watching the History Channel (though he's watching plenty of TV) and telling himself he wants to be just like Adolf Hitler or Idi Amin and hold dick-sucking rallies for himself.
It just comes naturally to the guy. That's the scary part.