Hugo Mercier in Persuasion:
After Donald Trump won the 2016 presidential election there was widespread suspicion that the results had been influenced by a Russian operation. The Internet Research Agency, a “troll factory” operating out of St Petersburg, was creating accounts posing as U.S. citizens or news agencies, posting thousands upon thousands of messages, the majority in support of Trump, and many fake. Could the Russians have pulled off something as big as swaying a U.S. election?
The answer has recently been confirmed: No. In January this year, a study by Gregory Eady, Tom Paskhalis, and their colleagues found that the majority (70%) of this Russian propaganda was consumed by only 1% of Twitter users, people who were already staunch Republicans and thus already overwhelmingly likely to vote for Trump. As a result, the fake news shared by the trolls merely preached to the choir. It doesn’t seem to have changed anyone’s mind.