Check out this excerpt from a Scott Aaronson blog in early June. I think it's pretty insightful.

R

Since Tao was criticized for not explicitly listing his reasons why Trump is unqualified, let me now give my own top ten—any one of which, in a sane world, I think would immediately disqualify Trump from presidential consideration.  To maximize the list’s appeal, I’ll restrict myself entirely to reasons that are about global security and the future of democratic norms, and not about which people or groups Trump hurled disgustingly unpresidential insults at (though obviously there’s also that).
1. He’s shown contempt for the First Amendment, by saying “libel laws should be opened up” to let him sue journalists who criticize him.
2. He’s shown contempt for an independent judiciary, and even lack of comprehension of the judiciary’s role in the US legal system.
3. He’s proposed a “temporary ban” on Muslims entering the US.  Even setting aside the moral and utilitarian costs, such a plan couldn’t possibly be implemented without giving religion an explicit role in the US legal system that the Constitution was largely written to prevent it from having.
4. He’s advocated ordering the military to murder the families of terrorists—the sort of thing that could precipitate a coup d’état if the military followed its own rules and refused.
5. He’s refused to rule out the tactical first use of nuclear weapons against ISIS.
6. He’s proposed walking away from the US’s defense alliances, which would probably force Japan, South Korea, and other countries to develop their own nuclear arsenals and set off a new round of nuclear proliferation.
7. He says that the national debt could be “paid back at a discount”—implicitly treating the US government like a failed casino project, and reneging on Alexander Hamilton’s principle (which has stood since the Revolutionary War, and helps maintain the world’s economic stability) that US credit is ironclad.
8. He’s repeatedly expressed admiration for autocrats, including Vladimir Putin and Kim Jong-un, as well as for the Chinese government’s decision to suppress the Tiananmen Square protests by arresting and killing thousands of people.
9. He’s expressed the desire to see people who protest his rallies “roughed up.”
10. He said that, not only would he walk away from the Paris accords, but the entire concept of global warming is a hoax invented by the Chinese.
Would Trump moderate his insane “policies” once elected?  I don’t know, but I’d say that electing someone who promises to ignore the rule of law, in the hope that they don’t really mean it, has one of the worst track records of any idea in human history.  Like, I acknowledge that a Trump presidency has a wide distribution over possible badnesses: whereas a Ted Cruz presidency would be pretty much a point distribution concentrated on “very bad,” a Trump presidency would have appreciable probability mass on “less bad than Cruz,” but also appreciable mass on “doesn’t even fit on the badness chart.”
Anyway, for these reasons and others, Shtetl-Optimized unhesitatingly endorses Hillary Clinton for president—and indeed, would continue to endorse Hillary if her next policy position was “eliminate all quantum computing research, except for that aiming to prove NP⊆BQP using D-Wave machines.”
Even so, there’s one crucial point on which I dissent from the consensus of my liberal friends.  Namely, my friends and colleagues constantly describe the rise of Trump as “incomprehensible”—or at best, as comprehensible only in terms of the US being full of racist, xenophobic redneck scumbags who were driven to shrieking rage by a black guy being elected president.  Which—OK, that’s one aspect of it, but it’s as if any attempt to dig deeper, to understand the roots of Trump’s appeal, if only to figure out how to defeat him, risks “someone mistaking you for the enemy.”
I remember watching the now-famous debate in August, where Megyn Kelly confronted Trump with his long history of derogatory comments about women, and Trump replied with a smirk, falsely claiming that his comments were “only [about] Rosie O’Donnell”—bringing down the house (both men and women) in laughter.  At that point, something clicked; I got it.  From then on, Trump’s continuing rise often scared or depressed me, but much less about it surprised me.
I think people support Trump for the same reason why second-graders support the class clown who calls the teacher a fart-brain to her face.  It’s not that the class literally agrees that the teacher’s cranium is filled with intestinal gases, or considers that an important question to raise.  It’s simply that the clown had the guts to stand up to this scolding authority figure who presumes to tell the class every day what they are and aren’t allowed to think.  (As far as I can tell, this has also been the central operating principle of right-wing shock artists over the decades, from Rush Limbaugh to Ann Coulter to Milo Yiannopoulos.)
Support for this thesis comes from r/The_Donald, the main online clearinghouse for Trump supporters.  Spend some time there, and many of the themes will be instantly recognizable if you’ve followed the interminable controversies about campus political correctness over the last few decades.  Perhaps the most popular theme is the self-referential one, of “refusing to be silenced” by the censorious Social Justice Warriors.  Trump supporters, for example, gleefully share articles about the university administrators and students who’ve treated “Trump 2016” and “Make America Great Again” chalked on campus sidewalks as hate crimes to be investigated and punished.
(Every time I read such a thing, I want to yell at the administrators and students involved: how can you not see that you’re playing directly into the other side’s narrative, giving them the PR bonanza of their dreams?  Actually, I’ve felt the same way about many left-wing campus antics since I was a teenager.)
I explained earlier how abysmally I think Trump comes across under the cold light of reason.  But how does he look to my inner five-year-old, or my inner self-serving orangutan?  Well, Trump’s campaign has attracted some noxious anti-Semites, who surely want me dead for that reason, but I see little indication that Trump himself, or most of his supporters, feel similarly.  I can’t say that they’ve said or done anything to threaten me personally.
Meanwhile, many of the social-justice types who are Trump’s ideological opposites did try to destroy my life—and not because I hurt anyone, tried to hurt anyone, or said anything false, but just because I went slightly outside their Overton Window while trying to foster empathy and dialogue and articulate something true.  And having spent a year and a half reading their shaming attacks, on Twitter, Tumblr, Metafilter, etc., I’m well-aware that many of them will try again to destroy me if they ever see an opportunity.
So on the purely personal level, you might say, I have a hundred times more reason to fear Amanda Marcotte than to fear Donald Trump, even though Trump might become the next Commander-in-Chief (!?), while Marcotte will never become more than a clickbait writer.  And you might add: if even a nerdy academic in Cambridge, MA, who’s supported gay rights and environmentalism and Democrats his whole life, is capable of feeling a twinge of vicarious satisfaction when Trump thumbs his nose at the social-justice bullies, then how much the more might a “middle American” feel that way?  Say, someone who worked his whole life to support a family, then lost his job at the plant, and who’s never experienced anything but derision, contempt, and accusations of unexamined white male privilege from university-educated coastal elites?
The truth is, there’s a movement that’s very effectively wielded social media to remake the public face of progressive activism—to the point where today, progressivism could strike an outside observer as being less about stopping climate change, raising the minimum wage, or investing in public transit than simply about ruining the lives of Brendan Eich and Matt Taylor and Tim Hunt and Erika Christakis and Dongle Guy and Elevator Guy and anyone else who tells the wrong joke, wears the wrong shirt, or sends the wrong email.  It strikes me that this movement never understood the extent to which progressive social values were already winning, with no need for this sort of vindictiveness.  It’s insisted instead on treating its vanquished culture-war enemies as shortsightedly as the Allies treated the Germans at Versailles.
So yes, I do think (as Bill Maher also said, before summarily reversing himself) that the bullying wing of the social-justice left bears at least some minor, indirect responsibility for the rise of Trump.  If you demonstrate enough times that even people who are trying to be decent will still get fired, jeered at, and publicly shamed over the tiniest ideological misstep, then eventually some of those who you’ve frightened might turn toward a demagogue who’s incapable of shame.