Margaret Sullivan writes: To save Tinkerbell, all you had to do was clap your hands and really, really believe in fairies.

To send a conspiracy theory on its vicious way around the world, you need to do more than just believe. You need help.

Luckily for those who wanted to elect Donald Trump, that help was available during the presidential campaign, and still is. It comes from a collection of new right-wing hyperpartisan media outlets that are having a huge effect on politics.

Consider, for example, one outlandish idea from just last week: that the CIA hacked the Democratic National Committee’s emails, gave them to WikiLeaks and then framed Russia.

Business Insider traced it: from replies to the WikiLeaks Twitter account, through conservative radio and then Breitbart News, and out into the semi-mainstream — Sean Hannity on Fox News — all within 48 hours.

Similarly, the right-wing radio host Mark Levin may have started the evidence-free idea that President Barack Obama ordered the wiretapping of now-President Trump. It made its way quickly through the media ecosystem, after Trump saw it, apparently on Breitbart News.

Once the president tweets it, it’s undeniably news, picked up everywhere and re-amplified — especially by right-wing sites.

Derek Thompson of the Atlantic called this a “conspiracy-theory feedback loop.” And a very effective one it is.

A major new study, published in Columbia Journalism Review, detailed just how influential the new media ecosystem has become, calling it a determining factor in Trump’s election. [Continue reading…]