The Atlantic devotes its December issue to that topic.
In my opinion, the article on social media as a cause for our national crisis, and the one on the defects in our nominating system as a cause for our national crisis, are interesting and instructive. But I do not think either article properly identifies the cause of our national crisis.
No, in my opinion, for what it may be worth, the piece by Adam Serwer accurately describes the root cause of our plight: “The true cause of American political discord is the lingering resistance of those who have traditionally held power to sharing it with those who until recently have only experienced its serrated edge.”
This analysis may be contrasted with another piece in the magazine, focusing on the urban versus rural, rich areas versus poor areas, better educated versus poorly educated splits as the root causes of Trumpism.
So, are people Trump supporters because they are racist, or because they are live in rural areas, are relatively poor, and lack education?
The best answer I can find is that they are Trump supporters because they are racists, because the world is changing in ways they can’t control, and because unscrupulous people have scared them witless.
The lead article in the issue—Yoni Appelbaum, How America Ends: A tectonic demographic shift is under way. Can the country hold together?—provides an admirable treatment, based on a deep dive into American history and recent comparative political studies. Mr. Appelbaum read the books, so you don’t have to.