A surprise appearance by Rep. Marjorie Taylor Greene (R-GA) at a white nationalist convention on Friday night presents a difficult test for Tucker Carlson, the Fox News star who has used his show to legitimize her as a mainstream political figure.

Greene spoke at the America First Political Action Conference organized by Nick Fuentes, a Holocaust denier and white nationalist who leads the extremist “groyper” movement. The event promoted attendance by a mix of white supremacist publishers, far-right conspiracy theorists, and Republican elected officials. 

Greene described the crowd during her speech as “canceled Americans” and said that they had “been handed the responsibility to fight for our Constitution and stand for our freedoms, and stop the Democrats who are the communist party of the United States of America.” Shortly before her speech, Fuentes asked for “a round of applause for Russia,” inciting cheers of “Putin, Putin”; speaking again following her remarks, he praised Adolf Hitler.

Pressed by reporters on Saturday about her appearance at the white nationalist event, Greene said that she was unfamiliar with Fuentes’ “views” and thus is “not aligned with anything that may be controversial.” This is not a credible explanation – her colleague, Rep. Paul Gosar (R-AZ) created a firestorm for attending the same conference in 2021.

Carlson has done more than virtually anyone to turn Greene from a fringe figure into a Republican rising star. The Fox host has praised her and defended her from accurate media portrayals as a conspiracy theorist, repeatedly given her a platform on his program, and even donated to her reelection campaign. Greene’s speech to a white nationalist convention puts him in a complicated position, particularly as it comes just weeks before his network launches its annual upfronts push to sell the bulk of its ads for the next year.

Greene is a toxic conspiracy theorist with a long record of bigoted anti-Muslim, antisemitic, and anti-trans commentary and violent rhetoric. Her support for the QAnon conspiracy theory, which posits that former President Donald Trump was secretly working to expose pedophile rings operated by a cabal of satanic government officials and celebrities, was known before she was elected to the U.S. House of Representatives.

But in January 2021, Media Matters revealed that she had also offered or endorsed the conspiracy theories that a deadly California forest fire had been ignited by a space laser triggered by a nefarious group of people including a vice chairman at “Rothschild Inc”; that the Parkland and Sandy Hook school shootings were false flags and the September 11 terror attack was an inside job; and that Hillary Clinton and former aide Huma Abedin sexually assaulted a child, filleted her face, wore her face like a mask, and then drank her blood as part of a satanic ritual to ingest something called adrenochrome. The same month, CNN uncovered comments from Greene in which she indicated her support for executing various Democrats.

These revelations ignited a media firestorm, generated condemnations of Greene from both Democrats and Republicans, and even helped fuel a House resolution seeking her expulsion from Congress. On February 4, 2021, the House voted to strip her of her committee assignments, with every Democrat and 11 House Republicans supporting the measure.

But three days before that vote – with Greene’s future in the House Republican caucus in jeopardy – Carlson came to her rescue. The Fox host, an influential figure in the GOP, told his viewers that Greene was being persecuted because CNN opposed her “views” and “bad opinions” – without revealing what she had actually supported. “Free inquiry is dead,” he blustered. “Unauthorized questions are hate speech.”

That monologue was the beginning of a year-long effort by Carlson to bring Greene into the mainstream of the Republican Party. He sought to minimize the criticisms she faces, while repeatedly hosting her for softball interviews on his program. 

Greene sat for an hour-long interview for Carlson’s streaming podcast, Tucker Carlson Today, in May 2021. “It occurred to us the other day, as much as we've heard about Marjorie Taylor Greene, we've never heard anything from Marjorie Taylor Greene, never met her, never talked to her,” he explained, promoting the interview on his Fox show. “I have no idea what she is really like, and it might be worth finding out.” He promised that viewers would learn “What it is like to be Marjorie Taylor Greene and be happy despite the attacks."

Carlson subsequently hosted Greene at least five times on his prime time show, using the appearances to laud Greene as a “Washington outsider” who “sees things that people have been around Washington a long time no longer notice” and to say of Democrats, “I hope they're afraid of you. They should be.” Together, they discussed topics including the January 6 select committee investigation; jailhouse conditions for people charged with crimes for their alleged actions during the January 6, 2021, insurrection; and her banning by Twitter for posting false information about the COVID-19 vaccines, which she described as “dangerous.”

When Twitter banned Greene, Carlson was irate that Republicans refused to “fight back." “No Republican has really come to Taylor Greene's defense, the House Minority Leader Kevin McCarthy issued a tepid statement, he did not even mention her name,” he said during a January 5 monologue.

Carlson has spent the last few years simultaneously channeling white nationalist talking points, courting white nationalist viewers, and denying that white nationalists play a meaningful role in American public life. Now a member of Congress that he ushered into the mainstream just got caught speaking to a convention of them. Will Carlson “fight back” and “come to Taylor Greene’s defense” and if so, how will he do it? Fox’s advertisers should take note.