Not too long ago, Tucker Carlson would go on vacation — always long-planned, of course — whenever one of his rancid descents into racism and white supremacy made life momentarily uncomfortable for his overlords at Fox News. He’d disappear for a few days, come back once the heat had died down and resume his hate-mongering ways.

But that was before former President Donald Trump’s lies about the 2020 election, before the insurrection of Jan. 6 and, most important, before Newsmax and One America News Network briefly put a scare into the Murdochs by showing that Fox’s audience, increasingly unmoored from reality, could no longer be taken for granted.

Thus we should have known that an uncontrite Carlson would be back at his perch Monday evening after enthusiastically endorsing “white replacement theory” the previous week. After all, Lachlan Murdoch, the heir to the throne, had defended Carlson earlier in the day in response to a letter from the Anti-Defamation League calling on Fox to fire its top-rated talk-show host.

“A full review of the guest interview indicates that Mr. Carlson decried and rejected replacement theory,” Murdoch said in his letter to ADL chief executive Jonathan Greenblatt. “As Mr. Carlson himself stated during the guest interview: ‘White replacement theory? No, no, this is a voting rights question.’”

This is how it works if you’re Tucker Carlson: You can express vile, unadorned racist views. And as long as you say the equivalent of “I’m not being racist,” you’re good to go. Or, rather, good to stay.

So what exactly happened last Thursday? Carlson popped up during the crossover from the 7 p.m. show to his own in order to banter with guest host Mark Steyn. Picking up on something Steyn had said earlier, Carlson excoriated Democrats for allowing immigrants into the country who would at some point be allowed to vote — thus diluting the votes of Americans who were already here.

“Now, I know that the left and all the little gatekeepers on Twitter become literally hysterical if you use the term ‘replacement,’ if you suggest that the Democratic Party is trying to replace the current electorate, the voters now casting ballots, with new people, more obedient voters from the Third World. But they become hysterical because that's what's happening, actually. Let's just say it: That's true,” Carlson said.

He then added the part that Lachlan Murdoch seems to think absolves him of racism: “Everyone wants to make a racial issue out of it. Oh, you know, the white replacement theory? No, no, no. This is a voting rights question. I have less political power because they are importing a brand new electorate. Why should I sit back and take that? The power that I have as an American guaranteed at birth is one man, one vote, and they are diluting it. No, they are not allowed to do it. Why are we putting up with this?”

This is, in fact, racism in its purest form: the belief that real Americans, defined by Carlson as people who were born here, have the right not to have to compete for political power with newcomers, and to be regarded as more worthy and more patriotic than those who immigrate here, become naturalized citizens and vote. Like, you know, Rupert Murdoch.

By the way, the aforementioned Steyn is a piece of work in his own right. A Canadian by way of the United Kingdom who once wrote dismissively of former Sen. Max Cleland’s devastating war injuries — the Georgia Democrat lost three limbs in Vietnam — Steyn came to Carlson’s defense in a post on his website.

Yet it wasn’t always sweetness and light between the two. In 2004, I wrote a profile of Steyn for The Boston Phoenix describing how he straddled the line between respectable conservatism and Ann Coulter-style gutter-dwelling. Steyn had criticized Carlson as a “conservative cutie” who had gone soft on the war in Iraq. So I called up Carlson, who had not yet begun his own descent into the intellectual abyss , and asked him what he thought.

“He’s kind of pompous,” Carlson said of Steyn. “He’s obviously smart, he can be quite witty. I mean, I agree with a lot of what he writes. But the problem with being a columnist for too long is that a) you tend to repeat yourself and b) you tend to forget that you need to marshal facts to support your opinions.”

But I digress. After all, this is about Carlson, who, no doubt charged up by Lachlan Murdoch’s endorsement, replayed his entire Thursday monologue to open his show on Monday and argued that he couldn’t possibly be racist because he believes the votes of Black people who were born in the U.S. are being diluted just as much as those of white people.

“Our leaders have no right to encourage foreigners to move to this country in order to change election results,” he said, and said this of Democrats: “Demographic replacement is their obsession because it’s their path to power.”

Not that any of this is new. The Atlantic’s Adam Serwer wrote about Carlson’s endorsement of white replacement theory back in 2018, after Carlson said that “Latin American countries are changing election outcomes here by forcing demographic change on this country.” That took place just a year after neo-Nazis in Charlottesville, Virginia — “very fine people,” as former President Donald Trump called them at the time — had chanted “Jews will not replace us! You will not replace us!”

So what is to be done? Advertisers have, on occasion, pulled out of Carlson’s show and other Fox programs. But that has a limited effect, since Fox makes most of its money from fees paid by the cable companies. As Angelo Carusone, president and CEO of the liberal media-watch organization Media Matters for America, recently told the public radio program “On The Media," “They can have zero commercials and still have a 90% profit margin because they are the second most expensive channel on everybody’s cable box."

That, in turn, has led the progressive media-form group Free Press to propose that Congress pass a law mandating à la carte cable service so that customers wouldn’t be forced to subsidize Fox and its ilk. That sounds promising, and I certainly wouldn’t mind not having to pay for the various flavors of ESPN. But I’m sure that such a move would have unintended consequences. For instance, how many people would choose to pay for CNN? Flawed though it is, it’s indispensable when there’s breaking news.

As for Carlson, nothing will change until, suddenly, it does. He may be the most powerful right-wing figure in the country right now — an heir to Trump and a possible future presidential candidate. Yet he’s playing with explosives, stirring up the hatred and resentment of his viewers in a way that could lead to some extremely ugly consequences.

Let’s hope it doesn’t come to that.

GBH News contributor Dan Kennedy’s blog, Media Nation, is online at dankennedy.net .