This post has been updated.

Tucker Carlson opened his show Monday night with a pointed message to his viewers.

“The left would very much like you to stop talking and thinking about bad decisions they’ve made over the years that they happen to be profiting from,” the Fox News host said. “ ‘Shut up,’ they’re screaming, including to this show. Obviously, we won’t, and you shouldn’t either.”

Carlson, who is facing a growing advertiser boycott over his recent remark that immigrants make the United States “poorer and dirtier and more divided,” devoted a segment of Monday’s show to doubling down on his controversial comments, which many have condemned as “racist.” In response to his immigration rhetoric, four companies have pulled their advertisements from Carlson’s prime-time show, The Washington Post’s Deanna Paul and Alex Horton reported Monday.

But rather than apologize, Carlson slammed the advertising backlash as an attack on free speech, telling his audience: “We’re not intimidated. We plan to say what’s true until the last day.”

In an email to The Post Tuesday morning, a Fox News spokesperson criticized the outrage as “unfortunate and unnecessary distractions,” noting that the network will “continue to stand by and work with our advertisers.”

“It is a shame that left-wing advocacy groups, under the guise of being supposed ‘media watchdogs,’ weaponize social media against companies in an effort to stifle free speech,” the statement said.

On Twitter, Carlson shared several clips from his Monday show, writing, “We spend a lot of time talking about the threat to free speech. It’s not an academic question. If they can force you to shut up, they will. Here’s their latest attempt.”

The segment began with Carlson revisiting past interviews with an elected official in Tijuana, who described how things in the city have been “getting worse” since the arrival of the Central American migrant caravan in November. As video footage showed what appeared to be giant piles of garbage in the streets amid haphazard rows of tents, the official reported that, in addition to the accumulation of trash, there have been “280 arrests” for offenses such as drug possession and breaking and entering into homes.

Carlson then proceeded to play the part of his monologue from Thursday’s show that sparked the advertising boycott, before reiterating his argument that it “could be preferable to import more engineers and fewer people with low skills, no matter how nice or well-meaning those people might be, and we always assume they are.”

“That’s what we said. That was our claim,” Carlson said. “It’s hard to argue with that. In fact, nobody on the left did argue with it. They ignored it.”

Instead, he said, critics “zeroed in on the last line” — his comment that the United States has a “moral obligation to admit the world’s poor . . . even if it makes our own country poorer and dirtier and more divided.”

Carlson went on to assert that his Thursday comments are “true,” using the scenes in Tijuana as evidence.

“But precisely because it is so obviously true, saying it out loud is a threat,” he said. “Our immigration policy exists for the profit and the comfort of a relatively tiny number of people. Everybody else gets shafted.”

He added: “Meanwhile, the people profiting from the policy don’t want the rest of us to think about it too much. They want us just to mouth the empty platitudes and move on. ‘Nothing to see here. Shut up and go away.’ Those who won’t shut up get silenced.”

People supporting the ad boycott, including producer Judd Apatow and Rep. Ted Lieu (D-Calif.), have excoriated Carlson for his “dirtier” comment, which one Twitter user described as “An offensive, dehumanizing and racist statement.”

Apatow, who has been actively tweeting at companies to pull their advertising, pointed out that “Everyone’s family is a family of immigrants.”

“How can anyone advertise on a show which spouts hate?” he wrote.

Lieu tweeted that he is an immigrant whose “parents were poor.”

“They worked hard and started a successful business,” he wrote, tagging Carlson. “Now their son is in Congress. So take your hatred of immigrants and shove it.”

Being silenced happens all too often to people who espouse controversial views, Carlson said Monday on his show. Carlson isn’t the first Fox News host to experience an advertiser exodus this year. In March, Laura Ingraham lost at least half a dozen advertisers after she taunted Parkland shooting survivor and activist David Hogg about his college acceptances. Within 24 hours of the boycott starting, Ingraham issued a public apology.

“You’ve seen it a million times,” Carlson said. “The enforcers scream, ‘Racist,’ on Twitter until everybody gets intimidated and changes the subject to the Russia investigation or some other distraction.”

The tactic may be “a well-worn one,” but Carlson said he doubted its effectiveness this time around. Several companies have stood behind their ad placement, including Bayer, producer of Alka-Seltzer Plus, Mitsubishi and Farmers Insurance, The Post reported.

“Nobody thinks it’s real, and it won’t work with this show,” Carlson said, before reaffirming his show’s dedication to “say what’s true.”

“And the truth is,” Carlson continued, “unregulated mass immigration has badly hurt this country’s natural landscape.”

Then, for roughly two minutes, Carlson laid out his argument for how illegal immigration has caused “huge swaths” of southwestern deserts in Arizona to become “covered with garbage and waste that degrade the soil and kill wildlife,” citing a 2002 report from the Government Accountability Office as well as various state officials.

“The left used to care about the environment,” Carlson said. “They understood that America is beautiful because it is open and uncrowded. Not so long ago, environmentalists opposed mass immigration. They knew what the costs were. They still know, but they don’t care. We do care, and we’re going to continue telling you about it. We think you have a right to know, no matter what they say.”

On social media, the segment was met largely with more calls for advertisers to leave Carlson’s show, and it appeared that at least one company was listening. Shortly after the show ended, Minted, an online marketplace for home goods, art and stationery, announced on Twitter it had “permanently discontinued advertising on this particular program.”

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