Why have the Democrats failed to offer a counternarrative to Trumpian nationalism? For two reasons, I think, one political and one moral.

First, these days nations often define their national identities through their immigration policies. Democrats have never liked to talk about immigration at election time. The immigration issue splits the Democratic coalition. Affluent progressive and liberal activists are for it, but working-class whites and African-Americans are more skeptical.

Moreover, those going to the polls in recent years who name immigration as their top issue tend to be much more restrictionist. If you’re a Democrat, you don’t get credit for being pro-immigrant from your friends, but you do get punished by your foes. So this year, as in past years, Democrats have tried to change the subject. In September, for example, 50 percent of the congressional pro-Democratic ads referred to health care. Only 4 percent mentioned immigration.

Second, over the last several years, Democrats have begun to think about nationalism and immigration differently.