David Goldman / AP

In Monday’s night 90-minute debate, Donald Trump barely made mention of an issue that has been the cornerstone of his presidential campaign since its launch: immigration.

The Republican nominee has touted his hardline stance on the issue on the campaign trail and on the primary debate stage next to his Republican opponents. But he left the matter untouched in the first debate with his Democratic rival, Hillary Clinton, despite numerous opportunities to it bring up.

Trump has called Mexican immigrants “rapists” and criminals. If elected, he’s said he would deport the 11 million undocumented immigrants in the United States. He has promised to build a wall on the southern border with Mexico, and to force that country to pay for it. He has said he would ban Muslims and refugees from Syria from entering the United States. All of those signature Trump proposals went unmentioned Monday night.

The closest Trump came to any of those issues during the debate was citing his recent endorsement by the National Immigration and Customs Enforcement Council, a union representing federal immigration officers. The endorsement came a few months after the National Border Patrol Council, a labor union representing more than 16,000 agents, also decided to back Trump. (Trump mistakenly said that ICE, the agency, had endorsed him, rather than the union representing ICE officers.)

That might have been an opportunity for Trump to plug his line that he would build a great wall on the U.S.-Mexico border that would be paid for by Mexico, but he refrained. By contrast, during the Republican primary debates, Trump frequently pounced on his opponents for their more lenient stances on immigration, like Jeb Bush, who supported a pathway to citizenship, and Marco Rubio, who was involved in the Gang of Eight legislation that would have granted legal status to millions of undocumented immigrants.

Trump also refrained from mentioning his stance on refugees. Late last year, more than half of the country’s governors—all of whom were Republican except one—urged the Obama administration to halt the resettlement of Syrian refugees.

During the debate, Trump charged that Clinton had been fighting ISIS her “entire adult life,” but did not mention the refugee issue. (ISIS has not been in existence for Clinton’s adult life.) While Trump has portrayed refugee resettlement as national security threat, only “three resettled refugees” out of the almost 800,000 brought to the U.S. since 2001 “have been arrested for planning terrorist activities,” according to the Migration Policy Institute.

Anti-immigrant voters have contributed to Trump’s surge. As Ronald Brownstein and Leah Askarinam reported in August: “Republicans who support deporting undocumented immigrants supplied Trump’s margin of victory in most of the key contests before he broke open the race in April.”

But on Monday night, Trump faced a far larger audience, some of whom could have been turned off by his hardline stance. Still, while he may have excluded his immigration talking points from the first presidential debate, they’re unlikely to be written off altogether.

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