The (partly German or Austrian) authors of "The Authoritarian Personality" had been asking the same question at the beginning of the 40s and found in their study that a preoccupingly high percentage of Americans are of the F-scale personality type (F like fascism), so prone to fall for autocratic or dictatorial systems and irrational and over-polarized ideology.
I think, however, that there are good reasons to believe that nowadays, things cant derail as they did in Germany at that time.
1. we have more experience with mass manipulation techniques
2. we can easily and quickly debunk wrong information given by anybody.
3. we get a much more complete picture of a public person nowadays.
3. we have a better understanding about socio-psychologic development (Piaget), psychology (Anna Freud: Ego defense mechanisms, Adler: compensation of a minority complex, others: neuroses), and the neurologic underpinnings of people who lack the power of judgement (Hannah Arendt: The Banality of Evil), an instrumenal reasoning (Dialectic of Enlightenment), and a propensity to develop individual or shared anxiety disorders.
4. it has gotten more difficult for people to consider themselves as superior, although they are actually cognitively challenged.
5. people have gotten much more aware of the vanity of the people who seek power, and dont fall for it that easily anymore. Charisma/demonic attraction is basically a phenomena of the past.
6. education is much less violent than it used to be, and values a little more the differences between children than it used to
I link the current hysteria to the hysteria about ASD epidemic and think that contrary to seemingly similar findings in history (Joachim Radkau, "The Age of Nervousness. Germany between Bismark an Hitler", the eugenic movement), this hysteria has a different, somewhat more entertaining and disillusionating quality, even with anxious-driven people. But even if things cant turn that bad, they might still go quite terribly wrong and a lot of harm can be either done - or avoided.
It would for example help a lot, if the US was capaple of modernizing their political system soon, and a majority would form and opt out of this debilitating two-party system with its focus on presidential power. That system of yours comes out of an historic period a modern democracy should have long left behind. It would be also good if the US would recognize themselves as a country with a higher than average degree of autism (due to being a migration society and due to more stress), to understand that stress is doing a lot of harm to people in general (and people on the spectrum in particular), and to take the necessary measures to lower stress.
I see it as very beneficial that third party candidates have gotten so much support and sympathy, in particular from younger voters, that Bernie Sanders policies attracted a lot of interest, that maternity leave and an employers attitude towards the parental duties of their employees have got a lot of attention, while the formerly very disputed health care reform has gotten much less.
That misogyny and rape culture gets so much attention is a very necessary part of the process, too. As is that much tougher regulation on gun control is not a taboo anymore. The true politial revolutions take always place in the private sphere first.
7. Women take a more active stand in politics.
8. ... and so should neurotypics.
Btw, I am neurotpyic, and this has a lot to do with why my answer to the question turns out more optimistic than that of others here.
For the broader perspective, I recommend "The Better Angels of Nature" from Stephen Pinter that has come to the same conclusion from a different (albeit at times a little faulty) way of reasoning, which might appeal more to pessimists than mine. The book takes a closer look at the long history of human violence, and comes to the - somewhat surprising, but comprehensible - conclusion that things have gotten better over the milleniums, as well as over the last centuries and decennies.