The most outlandish conspiracy theories often put a fun-house mirror in front of reality: you know that whatever’s being reflected is there in some form, but what you’re seeing is distorted to the point of absurdity. The QAnon “conspiracy” had a real-life counterpart in the sprawling Jeffrey Epstein underage sex-trafficking operation. Likewise, the idea that Ronald Reagan deliberately flooded inner cities with crack cocaine out of racism was an outlandish version of his very real use of drug money to fund the Nicaraguan contras in the 1980s.

It’s a similar situation with the 9/11 “truther” movement that sprung up in the wake of the September 11, 2001, attacks.

Though “truther” claims differ on the details —  were the attacks carried out via remote control or controlled demolition? Was war on Iraq the motivation, or was it a domestic power grab? —  the heart of the theories is that the attacks were knowingly orchestrated by President George W. Bush. By 2006, more than one-third of Americans polled still thought US officials helped or allowed the 9/11 attacks to happen in order to pave the way for war in the Middle East. One-fifth of people thought the same in 2003 Germany, where books making the case were bestsellers. As late as 2008, only 46 percent of respondents across seventeen countries fingered al-Qaeda as the culprit.