This article explains how the social media was corrupted with fake news orchestrated by Russia in the US election. Russians believe that the US uses the social media to influence opinion in Russia and that they are just retaliating. In any case, the fake media operated like a super PAC by providing millions of dollars worth of misinformation during the campaign. One of the fake news sites got more hits in the social media than CNN's site during the election campaign.
In addition to operating fake news sites thousands of trolls were employed to comment on US media sites. If your read the comments following this article you will find that the Washington Post is described as a fake news site by the trolls who are frequent contributors to the Post's comment sections. If the intent of some fake news sites (many are just in it for the money} is to promote conspiracy theories that weaken our democracy it has worked. The social media have replaced responsible journalism as a source of information for many Americans.