Two scholars who specialize in media propaganda analyze the consequences of Trump retweeting an image with an inaccurate caption (which recontextualized a mentally ill person’s action, presenting it to Trump’s followers as a racially motivated act by a #blm supporter).

On Sunday night, President Donald Trump retweeted a video of a violent incident on a New York City subway platform. The video shows a Black man pushing a white woman into a train car and is captioned “Black Lives Matter / Antifa.” The problem? It is over a year old and has nothing to do with either Black Lives Matter or Antifa. It, in fact, shows the actions of a mentally ill man with no known ties to either group.

Trump’s Sunday night retweet is a case study in how far-right online networks work across social media platforms to build their followings, promote their messages, and provide Trump with the viral content that filled his timeline on Sunday.

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The mislabeled, repurposed clip that Trump retweeted originated from the account of an individual calling himself “I’m with Groyper”—an indication that he self-identifies as a member of the Groyper Army, which the Anti-Defamation League describes as a loose network of online white supremacists. That video was seized upon by TDN_NOTICIAS, which posted it on Sunday with the caption “Black Lives Matter / Antifa.”  Approximately an hour and a half after TDN_NOTICIAS posted it, Trump retweeted it.\

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While “I’m With Groyper” has been removed from Twitter, TDN_NOTICIAS has escaped punishment, but not notice, and has ultimately benefited from this entire episode. In the course of a day, TDN_NOTICIAS followed more than 460 new accounts, gained 600 followers, and received, in one tweet, engagement far greater than anything else they had ever produced. The tweet before the Trump retweet had 108 retweets and 129 likes. The Trump retweet garnered 20.1K likes and 12.5K retweets, the tweet after it 153 likes and 60 retweets. It is possible that TDN_NOTICIAS, finding no profitability in a click bait veneer of a news organization, has been spamming pro-Trump content with the goal of achieving this sort of notoriety.

Source: How hate and misinformation go viral: A case study of a Trump retweet