Fox News' Tucker Carlson has been even more controversial than usual lately, promoting the racist Replacement Theory on his show and expressing sympathy for the violent mob that assaulted the U.S. Capitol Building on January 6 — and Anti-Defamation League National Director Jonathan Greenblatt is calling for Fox News to fire him. During an appearance on CNN's "Reliable Sources," Greenblatt and host Brian Stelter agreed: Carlson is out of control.

A conspiracy theory that is popular among White supremacists and White nationalists, the Replacement Theory claims that liberals and progressives are trying to "replace" Whites with non-Whites by bringing them in from developing countries. Carlson, on his April 8 broadcast, claimed that "the Democratic Party is trying to replace the current electorate" with "new people, more obedient voters from the Third World."

Stelter acknowledged that it is most unlikely that Fox News will fire Carlson, whose "Tucker Carlson Tonight" has been getting even higher ratings than colleague Sean Hannity's show. But he stressed that Carlson reached a "new low" by promoting a conspiracy theory associated with White supremacist and White nationalist ideology.

The ADL director told Stelter, "Tucker Carlson has a history of sanitizing stereotypes and of spreading this kind of poison. But what he did on Thursday night really was, as you put it, a new low. The Great Replacement Theory, as it's known, is this toxic idea that there are a cabal of Jews plotting to overrun the country with immigrants, Muslims, Black people, etc. and commit what they call White genocide. It is literally, Brian, a staple of White supremacist and extremist ideology. And so, when Tucker Carlson literally introduces it to his four and one-half million viewers, he's serving as a gateway to one of the most damaging and dangerous conspiracy theories out there."

Greenblatt noted that during the Unite the Right Rally in Charlottesville, Virginia in 2017 — where an act of domestic terrorism killed activist/counterdemonstrator Heather Heyer — groups of White supremacists were chanting, "Jews will not replace us." And Greenblatt added that the Replacement Theory also inspired domestic terrorist attacks in El Paso and Pittsburgh.

"Again and again and again," Greenblatt told Stelter, "it is the Replacement Theory that has been invoked by these extremist murderers. So, when Tucker Carlson invokes it on his show — when he dismisses it — it is so dangerous…. We've really crossed a new threshold when a major news network dismisses this or pretends like it isn't important. So, number one: Tucker has got to go."