Ask the questions about right-wing terrorists that we ask about Islamist militants

Naturally, when Sayoc sent letter bombs to Trump’s critics, the right-wing media claimed it must be a “false flag” operation. Once the preserve of the paranoid radio host Alex Jones, this lunacy is now propagated by the likes of Ann Coulter, Rush Limbaugh, Dinesh D’Souza, Frank Gaffney, Donald Trump Jr. and Michael Savage. D’Souza tweeted: “Fake sexual assault victims. Fake refugees. Now fake mail bombs. We are all learning how the media left are masters of distortion, deflection & deception.” Trump himself appeared to give winking support to this crackpot theory by referring to “this ‘Bomb’ stuff.” Even after Sayoc’s arrest, few “false flag” theorists recanted or apologized.

There is partisanship on both sides of the political spectrum, but no left-wing outlets propagate extremism as successfully or widely as conservative media do. A new study of “Network Propaganda” by three Harvard researchers notes that liberals, by and large, get their news from sources such as The Post, the Times, NPR and CNN that, regardless of any political bias, also engage in rigorous fact-checking. Conservatives, by contrast, are being brainwashed by right-wing media that are an “echo chamber” for “rumor and conspiracy theory.”