Many constituencies in this country have been steadily ghettoized in this way; we’ve just failed to notice. On so many critical issues, like the Iraq war, abortion rights and gun control, the majority popular opinion has gone ignored, especially by Republicans. As the party has increasingly kowtowed to donors and to a small but influential voter base, the will of the rest of the people has become an inconvenience. It’s a metaphorical eyesore, a neighborhood to drive through with the windows up.

White people don’t frame this kind of negligence as racial, but they should. Blacks do because they’ve lived the negligence, and still live it. (We live in a hypocrisy, not a democracy, as Malcolm X once said). Blacks have always known that America is very good at ghettoizing, at separating influencers from losers. It’s in our DNA to keep certain folks at the margins.

Unfortunately, Americans are also very good at denying this truth, mostly because it conflicts with our democratic ideals. But even the most idealistic among us tend to see inner cities as Mr. Trump sees them — intractable, lowest on the totem pole, forever on the wrong side of the dividing line. We may be scandalized by Mr. Trump’s segregationist logic, but the logic is easy to follow. A world organized into essential and nonessential people makes sense in America, and always has.

The biggest paradox is that the working class and poor white people who have been ghettoized by deindustrialization and outsourcing are among Mr. Trump’s staunchest supporters. They think they still live in a hallowed space because the president actually visits them. He holds rallies with them. He goes to their neighborhoods, he seeks them out and he pointedly includes them in his favorite pronoun, “we.” He flatters them with the idea that he’s one of their tribe.

And as a white man, he is. But despite the appearance of favoritism, white working class Americans are as politically marginalized as Mr. Trump’s critics; they’re in the ghetto, too. If they could realize that, the oppressed in this country might make common cause, might find strength in numbers and in a diversity it’s never had. The lowly ghetto, in other words, might finally rise up.