Fox News-host Tucker Carlson, whose show is the most-watched news program on cable, used part of his segment Monday night to rail against immigration by talking about the dangers of “changing demographics in America.”

He used the example of a former coal mining town in Pennsylvania, called Hazleton, whose Hispanic population grew from 5% in 2000 to 52% in 2010. Carlson said Americans are “bewildered” by the change: “No nation, no society, has ever changed this much, this fast.”

“People who grew up in Hazleton return to find out they can’t communicate with the people who now live there. And that’s bewildering for people. That’s happening all over the country,” Carlson said. “This is more change than human beings are designed to digest.”

He also asked viewers: “How would you feel if that happened in your neighborhood?”

Since replacing Bill O’Reilly on Fox News’ top slot nearly a year ago, Carlson has made headlines for his increasingly inflammatory rhetoric, especially when it comes to immigrants. He often highlights crimes committed by immigrants, for instance, and bashes politicians pushing for immigration reform.

Where Carlson differs from most other conservatives, however, is that he does not hide his larger beliefs about ethnic nationalism, arguing in numerous instances that multiculturalism has been the country’s downfall. He has not reserved his criticism of immigrants just to undocumented immigrants—he has repeatedly railed against legal immigration, too. That's in line with the extremist stance taken by many in the Trump administration, namely senior advisor for policy Stephen Miller.

Critics of the hard line on immigration point out that demographic change is nothing new to the United States. In fact, since its inception the country has been transformed by successive waves of immigrants, and it's part of its heritage beginning with Native Americans.

“The less we have in common the stronger we are?” Carlson asked sarcastically in a January segment, in response to the widely held belief that the United States is a country made up of ideals, and that diversity is a strength. “Is a marriage stronger when spouses have radically different beliefs? Are you closer to your kids when you share no common points of reference?”

In a tweet Wednesday, Mic senior writer Jack Smith IV called Carlson’s Monday segment “white nationalist TV.”

Carlson has received the applause of overt white supremacists before, including from alt-right leader Richard Spencer and former Ku Klux Klan grand wizard David Duke. Both argue that immigrants are a threat to “Western civilization.”

In a January appearance on CNBC, conservative pundit Bill Kristol said that he could no longer defend Carlson’s show.

"I mean, it is close now to racism, white—I mean, I don't know if it's racism exactly—but ethno-nationalism of some kind, let's call it,” he said.

In Monday’s segment, Carlson also suggested that many politicians protect themselves from diversity by living in neighborhoods that remain “unchanged” from the 1960s.

“They caused all of this with their reckless immigration policies … and yet their own neighborhoods are basically unchanged – they look like it’s 1960,” he said. “Our leaders are for diversity, just not where they live.”