It was a debate with several ugly moments. Chris Christie called President Obama a “petulant child” and vowed to “kick” his “rear end out of the White House come this fall,” evidently forgetting that the man he once hugged is leaving at the end of this year anyway. Ben Carson said “secular progressives” don’t know “there is such a thing as right and wrong.” Ted Cruz called Obama a “child” too.

But the ugliest moments belonged to Marco Rubio. The junior senator from Florida sold his soul in North Charleston, South Carolina, for a shot at winning over the supporters of Donald Trump.   

It began early in the night when Rubio said, “Barack Obama does not believe that America is a great global power. Barack Obama believes that America is a arrogant global power that needs to be cut down to size.” These are lies. Since becoming a national political figure roughly a decade ago, Obama has uttered millions of words about America. In addition to his public statements, his private comments have made it into the media countless times. He’s never said anything remotely like what Rubio suggests.

If he had, Rubio would have quoted him. Obama’s view is clear: He thinks America will be a “great[er] global power” if it avoids expending large quantities of blood and treasure in countries whose internal problems America cannot solve at the point of a gun. Rubio disagrees with that view, which is fine. His problem is that in a party in which more than 60 percent of the voters don’t think Obama loves America, disagreeing is not enough. So Rubio has begun suggesting that Obama is some kind of Manchurian (or perhaps Mauritanian) candidate, actively seeking to do America ill. Earlier this month, he claimed the president has “deliberately weakened America.” Donald Trump said Obama’s passport wasn’t American. Now, to compete with Trump, Rubio is saying Obama’s heart isn’t American.

Later in the evening, the moderators asked about Trump’s proposal to ban Muslims from entering the United States. Christie and John Kasich said they disagreed. Jeb Bush disagreed at length. Rubio did not. Instead, he began his answer by praising Trump for having “tapped in to some of that anger that’s out there about this whole issue because this president has consistently underestimated the threat of ISIS.” Then, after talking about how awful ISIS is, Rubio declared that, “When I’m president. If we do not know who you are, and we do not know why you are coming when I am president, you are not getting into the United States of America.” The listener who didn’t already know Rubio’s position might well have thought he supports Trump’s plan.

This is the Florida senator’s new strategy. He doesn’t reject Trump’s bigotry; he piggybacks on it. When asked in late November about Trump’s call for closing mosques, Rubio said, “It’s not about closing down mosques. It’s about closing down any place—whether it’s a cafe, a diner, an Internet site—any place where radicals are being inspired.” In other words, Trump didn’t go far enough.

But Rubio’s worst moment came near the debate’s end, when Maria Bartiromo asked why the bill he cosponsored in the Senate would have distributed 10 million new green cards over 10 years. For years now, the Ann Coulter wing of the Republican Party has been pillorying Rubio for having supported a path to citizenship for undocumented immigrants. But Bartiromo’s question wasn’t about that. It was about legal immigration, the virtues of which Rubio has made central to his political being. When profiled on the cover of Time in 2013, Rubio let it be known that his mother had told him in Spanish, “Don’t mess with the immigrants, my son...They’re human beings just like us, and they came for the same reasons we came. To work. To improve their lives. So please, don’t mess with them.”

But the people Rubio needs to win don’t only dislike undocumented immigration. They dislike any immigration that involves swarthy faces and Spanish accents. In her proudly racist book, Adios America, from which Trump borrowed the material about Mexicans and rape, Coulter warns repeatedly about the “browning” and “shortening” of America. According to a Pew Research Center poll in September, 71 percent of Republicans think immigrants increase crime and 81 percent say immigrants don’t assimilate.

So instead of defending his past support of legal immigration, Rubio abandoned it. “The issue is a dramatically different issue than it was 24 months ago,” he began. “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.” Rubio didn’t explain what exactly that means but the implication is that because of ISIS, he would be far stingier about who can legally enter the United States. Back in 2013, when nativist Iowa Congressman Steve King tried to use the Boston marathon bombing as a pretext to limit legal immigration, Rubio responded that, “We should really be very cautious about using language that links these two things in any way.” Not anymore. Now Rubio is worried that the women and children fleeing rape and murder in Guatemala are trying to establish a caliphate in Southern California.

Intellectually, Rubio’s answer was pitiful. ISIS has been around since he launched his presidential campaign, but only now, with Trump and Cruz beating him in the polls, is he using it as an excuse to restrict legal immigration. Nor did ISIS invent the possibility that jihadist terrorists might get visas. All 19 men who brought down the Twin Towers entered the United States legally. In reality, Rubio’s answer has nothing do with ISIS and everything to do with the fact that, having planned to run as the man who could help Republicans embrace multicultural America, he now realizes that most of them want to build a wall to keep it.

So, Rubio, belatedly, is trying to be their man. The contrast with Jeb Bush is striking. For months now, Bush has been Trump’s punching bag. His inability to convert his vast fundraising haul into voter support has made him a political laughingstock. Yet on the stage in North Charleston, Bush showed some decency, maybe even courage. Asked about Trump’s plan to impose a religious test on entering the country, he warned that, “You cannot make rash statements and expect the rest of the world to respond as though, well, it’s just politics. Every time we send signals like this, we send a signal of weakness, not strength.”

But for Rubio, it is just politics. Unlike Bush, he possesses the political talent to effectively challenge the paranoia and bigotry coursing through today’s GOP. Instead, he’s rolled over. At the debate, he left absolutely no doubt: His strategy for defeating Trump is to ape Trump. Bush may have lost the debate, as he has lost every debate, but he lost with dignity. Rubio surrendered his. And he probably lost anyway. Despite his best efforts, he just doesn’t do fear and hatred that well.