This is what most regimes and "leaders" don't understand. They think that if they were put/elected there by some people then those are the only ones they have to serve. They do not acknowledge that they should serve the country. As such the disenfranchised start to think that if the power isn't on their side, the complete opposite must be. They drift towards an extreme, whatever that may be since both left and right extremes are very closer to each other - they justify the same things for different reasons.
Once enough are disenfranchised the power balance shifts. But the next to come in power will do the same, this time with the "moral" justification that the others deserve to be punished, swinging the pendulum further to the opposite side. If you repeat this cycle a few times you get to the pendulum's breaking point.
A president with a terrible character to begin with will just fast track the pendulum in one swing. They will add fuel to the fire and watch it burn not only out of pleasure or frustration, but also ineptitude.
I think the original deal of public education was to establish a realistic way to do this. IMO the over focus on the shared benefit of raising income/GDP as the benefit has compromised the long term sustainability of the system.
I have no clue but have always wondered
This is a particular point of the "kettling" tactic, where protestors are herded into an area and kept there for hours.
No government stands a chance if an any much significant part of population raises against it. I'm not even saying a majority.
What we saw today in DC was not a big rally.
A big rally would look like this: https://i.tribune.com.pk/media/images/Khadim-Rizvi-funeral-2... and like that for a few more city blocks.
Or like this: https://cdn.theatlantic.com/static/infocus/moscow1991/AP9103...
Or this: https://static.toiimg.com/img/67604038/Master.jpg
Learning living along with the radicals is a good alternative to having a war with them.