You can learn a lot from the words politicians use, and even more from the words they don’t. At last night’s Republican debate, candidates and moderators mentioned “immigration” 27 times. No surprise there. It may the single biggest issue in the GOP race. The word “Mexican,” however, wasn’t mentioned once, even though in recent years Mexicans have constituted America’s largest immigrant group. Neither did anyone mention “Chinese, Indian, Filipino, Vietnamese or El Salvadoran,” the other most common nationalities of recent immigrants. “Latino” was never mentioned. Neither was “Asian.” “Hispanic” was mentioned once.

“Muslim,” by contrast, was mentioned 15 times, often preceded by the adjective “radical.” The word “Islam” was cited nine times. “ISIS” came up a whopping 45 times.

This is partly because the candidates were asked about events in the Middle East. But it’s also because they repeatedly turned questions about immigration into questions about Muslims and ISIS. A Mexican American businesswoman asked Ben Carson, “If America does not seem like a welcoming place for immigrant entrepreneurs, will the American economy suffer?” Carson replied that, “We have to be intelligent about the way that we form our immigration policies, and that’s one of the reasons that I have called on us to declare war on the Islamic State because we need to reorient our immigration policies and our visa policies for people who are coming into this country because there are many people out there who want to destroy us.”

Megyn Kelly asked Marco Rubio about the problem of undocumented immigrants. He responded that, “I’m going to tell you exactly how we’re going to deal with it when I am president. Number one, we’re going to keep ISIS out of America.”

It’s been like this at every GOP debate. On December 15, Donald Trump declared that, “People are pouring across the southern border. I will build a wall ... As far as other people like in the migration, where they’re going, tens of thousands of people having cell phones with ISIS flags on them? I don’t think so.” On January 14, moderator Maria Bartiromo asked Rubio why he cosponsored a Senate bill that would have distributed 10 million new green cards. He responded that, “The issue is a dramatically different issue than it was 24 months ago. Twenty-four months ago, 36 months ago, you did not have a group of radical crazies named ISIS ... The entire system of legal immigration must now be reexamined for security first and foremost.”

As public policy, this makes little sense. Obviously, the United States should take care not to admit jihadist terrorists. But since would-be terrorists constitute a miniscule percentage of newcomers to the United States, drastically reducing legal immigration—or not granting the undocumented citizenship—in order to prevent ISIS members from entering America is like using a sledgehammer to squash a fly. It’s the equivalent of declaring that because terrorists could put a bomb in a cargo bin, the U.S. will slash its import of foreign goods.

But politically, it serves a purpose. By putting ISIS at the center of their immigration rhetoric, Republican candidates make immigration seem more threatening and less ambiguous. It’s one thing to depict immigrants as people who depress wages and crowd schools. It’s another to depict them as potential killers. That utterly dehumanizes them.

The answers by GOP candidates also play into a larger conservative effort to depict Mexican immigrants as, if not ISIS members, then at least dangerous. Immigrants actually commit crime at a lower rate than native-born Americans. Still, Donald Trump last year called Mexican immigrants “rapists,” a charge he gleaned from Ann Coulter’s book, Adios America, which in grizzly detail recounts example after example of swarthy immigrants committing acts of violence. “There is so much fixation on, for example, beheadings by ISIS,” Coulter declared last summer. “Well, the champion beheaders are Mexicans. They pioneered the practice of putting videotaped beheadings on television.”

In 2014, Jeb Bush got into trouble for calling immigration an “act of love.” No Republican contender would say that now. But today’s candidates aren’t even content to depict it as an act of self-interest. By constantly invoking ISIS and terrorism, they associate immigration with violence and hatred. And in so doing, they make it easier for Americans to respond with hatred of their own.