Special Counsel Robert Mueller released a bombshell indictment Friday, implicating 13 Russian nationals and detailing a multi-year, costly, and widespread effort to influence the 2016 presidential election. At the center of that effort were Facebook and its subsidiary Instagram, which the Russian Internet Research Agency (IRA) used to recruit American followers, plan real-life rallies, and spread propaganda about issues like religion, immigration, and eventually Hillary Clinton and Donald Trump.