Reprinted with permission from Media Matters

In the wake of the September 11, 2001, terrorist attacks came the so-called "9/11 Truth" movement, whose adherents claimed that the attacks had actually been an "inside job" perpetrated by the U.S. government. This crackpottery had few prominent advocates, but enough Americans bought into it to lift up people like Alex Jones, the conspiracy theorist radio host who has claimed that the feds used "controlled demolitions" to bring down the World Trade Center and whose website has described him as one of the "founding fathers" of the movement.

Nearly two decades later, the January 6 storming of the U.S. Capitol by violent Trumpists has generated new cries of an inside job. But this time, the conspiracy theory is backed by the most-watched host on cable news, Fox News prime-time star Tucker Carlson.

On Tuesday, Carlson alleged that "some of the key people who participated on January 6 have not been charged," citing charging documents in which "the government calls those people unindicted co-conspirators." He then exclaimed: "What does that mean? Well, it means that in potentially every single case they were FBI operatives. Really? In the Capitol on January 6?"

Carlson was citing a report from Revolver News' Darren Beattie, who he then brought on. Beattie is not a credible source -- he left his job at the Trump White House after CNN asked about him speaking at a 2016 conference alongside well-known white nationalists. But even Beattie suggested that Carlson was taking his work too far -- when Carlson said that his piece explains that "the FBI was organizing the riots of January 6," he replied that it only "suggests that possibility."

In fact, this theory, which rests on the premise that "unindicted co-conspirators" are by definition "FBI operatives," collapses with the slightest scrutiny, and suggests that Carlson either a) lacks a basic understanding of federal investigations or b) thinks his viewers are rubes.

"Legal experts say the government literally cannot name an undercover agent as an unindicted co-conspirator," The Washington Post's Aaron Blake reported in a filleting of Carlson's segment, pointing out that better explanations for the unindicted conspirators include that they might be cooperating with the federal government. Blake noted that while it's not literally impossible that the government is violating that stricture, there's also no evidence to believe that is the case.

But Carlson doubled down on Wednesday, stating as fact, "The events of January 6 ... were at least in part organized and carried out in secret by people connected to federal law enforcement." Again, there's no evidence at all for this, but Carlson nonetheless said, "It's hard to think of a bigger potential scandal than this one." Taking the conspiracy theory a step further, he went on to allege that the government won't release Capitol surveillance footage of the riot because "people they know are on the tape."

Carlson is one of the most powerful figures in the modern right. He is the face of Fox and an increasingly influential force in Republican politics. When he takes a stand, others follow. His January 6 conspiracy theory quickly drew support from far-right influencers and media figures and even GOP members of Congress.

The Fox host's "false flag" theory fits into a broad and largely successful effort by elements of the GOP and right-wing press to confuse the public and shatter the initial, fragile consensus that the events of January 6 had been bad and reflected poorly on then-President Donald Trump and his supporters.

Carlson himself has sought to create an alternate-reality version of the events of the day, denying that it was an "insurrection" that featured the involvement of violent right-wingers including Proud Boys and white supremacists.

In his initial response to the riots, Carlson validated the concerns of the perpetrators, but nonetheless said that they went too far.

"What happened at the Capitol last Wednesday was wrong," he said on January 14. "We've said that very clearly at the time. We've said it very clearly every day since. And we'll continue to say it."

But he did not continue to say it. As those events passed further into memory, he shifted how he talked about them. Here's how he started his April 6 broadcast, in a monologue dripping with sarcasm:

Today is the three-month anniversary of January 6. For those of you who aren't good at dates or don't have calendars, this is the day that we pause to remember the white supremacist QAnon insurrection that came so very close to toppling our government and ending this democracy forever.
You saw what happened. It was carried live on television, every gruesome moment. A mob of older people from unfashionable ZIP codes somehow made it all the way to Washington, D.C., probably by bus.
They wandered freely through the Capitol like it was their building or something. They didn't have guns, but a lot of them had extremely dangerous ideas. They talked about the Constitution and something called their rights.
Some of them made openly seditious claims. They insisted, for example, that the last election was not entirely fair. The whole thing was terrifying.

And now, Carlson has become a founding father of the 1/6 Truth movement. It's winning him plaudits from his predecessor, Jones, who took credit on Wednesday for alerting Carlson to Beattie's story. That could be a lie -- Jones is a liar, after all -- but Carlson has previously sourced footage from one of Jones' employees, and he appeared regularly on Jones' show as recently as 2015.

"I made the decision not to get into this until it broke on Tucker because I thought he'd do a better job than I did," Jones explained. "He did. He did a great job."

Shortly after, he brought on Beattie to discuss the same theory he had detailed for Fox's audience.