washington — four minutes into a video that was posted on instagram last month, justin bieber leaned into the camera and adjusted the front of his black knit beanie. for some of his 130 million followers, it was a signal.  in the video, someone had posted a comment asking mr. bieber to touch his hat if he had been a victim of a child-trafficking ring known as pizzagate. thousands of comments were flooding in, and there was no evidence that mr. bieber had seen that message. but the pop star’s innocuous gesture set off a flurry of online activity, which highlighted the resurgence of one of social media’s early conspiracy theories.  viewers quickly uploaded hundreds of videos online analyzing mr. bieber’s action. the videos were translated into spanish, portuguese and other languages, amassing millions of views. fans then left thousands of comments on mr. bieber’s social media posts asking him if he was safe. within days, searches for “justin and pizzagate” soared on google, and the hashtag #savebieber started trending.  four years ago, ahead of the 2016 presidential election, the baseless notion that hillary clinton and democratic elites were running a child sex-trafficking ring out of a washington pizzeria spread across the internet, illustrating how a crackpot idea with no truth to it could blossom on social media — and how dangerous it could be. in december 2016, a vigilante gunman showed up at the restaurant with an assault rifle and opened fire into a closet.
‘pizzagate’ conspiracy theory thrives anew in the tiktok era