But the liberal impulse at the moment, Buttigiegian as well as Ocasio-Cortezan, is to insist that liberalism is a seamless garment, an indivisible agenda that need not be compromised on any front. And instead of recognizing populism as a motley coalition united primarily by opposition to liberalism’s rule, liberals want to believe they’re facing a unitary enemy — a revanchist patriarchal white supremacy, infecting every branch and tributary of the right.

In this view it’s not enough to see racial resentment as one important form of anti-liberalism (which it surely is); all anti-liberalism must fall under the canopy. Libertarianism is white supremacy, the N.R.A. is white supremacy, immigration skepticism is white supremacy, tax-sensitive suburbia is white supremacy, the pro-life movement is white supremacy, anxiety about terrorism is white supremacy … and you can’t compromise with white supremacists, you can only crush them.

Which liberals may do in 2020, because Trump remains eminently beatable. But in the long run, the global trend suggests that a liberalism that remains inflexible in the face of variegated resistance is the ideology more likely to be crushed.