When commentators dismiss such concerns as “mere semantics,” they mean to say: “This is a futile, pointless discussion.”

That’s a mistake. Semantics is the branch of linguistics and logic that deals with meaning. When we argue over what to call a crime like the stabbings in St. Cloud and the bombings in New York and New Jersey, we are arguing over what they mean. That’s a supremely important conversation.

Last year, a distinguished French philosopher named Pierre Manent attempted to offer an answer in a book-length essay, Beyond Radical Secularism. He began writing after the Charlie Hebdo attacks in January 2015, and published just before the atrocious mass murders of November 2015.

The book was very widely debated and discussed in France. Americans may have more trouble assimilating it, because of its very French style. Beyond Radical Secularism is a book of bold assertions and heroic generalizations. We flinch from those on the western side of the Atlantic (if I may hazard a bold assertion and heroic generalization of my own). But if we flinch in this case, we’ll miss something important—not only to our French friends and partners, but to ourselves.

Pierre Manent writes: “If, in order to analyze the same phenomenon, one person repeatedly uses the word ‘Islam,’ whereas another recommends above all that this word be avoided, it is clear that we are condemning ourselves to going around in a sterile circle, and not without the ritual exchange of offensive epithets.”

Manent is one of those who want to use the word “Islam,” not in order to blame or condemn a group of people (he very sedulously refrains from doing anything like that), but in order to identify more precisely the challenge Western societies face in consequence of the large-scale migration from Muslim-majority lands. The French version of the challenge is particularly extreme: It has entailed not only spectacular acts of terrorism, but a proliferation of lower-intensity confrontations between Muslim citizens and state authority. One view, often heard in the United States, attributes France’s difficulties with Muslim migration not to the migration, but to the society receiving the migration.

“France seems to alienate many more of its citizens and residents, well beyond those who actually join the Islamic State,” wrote the sociologist Farhad Khosrokhavar in The New York Times in July 2016. Khosrokhavar’s explanation of this alienation will sound familiar, for it is often heard in the United States:

Britain and Germany give non-local minorities ample leeway to publicly express and practice their religious and communal preferences. France insists—in the name of republicanism—that religion should remain a strictly private affair. An ideological nation par excellence, it focuses on symbolic issues like wearing headscarves or holding collective prayers in public places.

This is a reassuring message, if not for the French, then for everybody else. Avoid French mistakes, and you avoid French results. Only … other nations are experiencing French results, in lesser degrees—the United States very much included. Alongside the roster of terrorist crimes over the past decade should be considered the longer tally of failed, foiled, or botched attempts: a car bomb in Times Square, a model-aircraft bomb allegedly destined for the Pentagon, and so on. These attempts often look incompetent, even ridiculous, after they are thwarted. Unlike the terrorists of 15 years ago, the people involved in such plots in the United States operate with much less, if any, support from international networks. Yet what they do indicate is that the difference between the French and other Western countries may be explained less in terms of France’s Revolutionary tradition, much more in terms of France’s—until recently—much larger Muslim minority population (almost 8 percent). As migration has recently swelled Muslim minority populations in Sweden and Germany, they too have experienced higher levels of alienation and conflict, most notoriously the New Year’s Eve sexual assaults of December 31, 2015.