This article is part of the Opinion Today newsletter. You can sign up here to receive the newsletter each weekday.

This is one of those weeks when President Trump’s campaign to discredit any independent source of information has been especially chilling.

It’s a classic tactic of autocrats. While he has not succeeded to anywhere near the degree that true autocra ts in other countries have, his continuing attempts at disinformation are still deeply alarming.

He has persuaded large numbers of Americans to believe almost anything that he or his allies say, regardless of how disconnected from reality it is. In the process, he is undercutting our democracy. In the last 48 hours alone:

Trump said on Twitter that Jeff Sessions, the attorney general, “should stop this Rigged Witch Hunt right now,” referring to Robert Mueller’s investigation, which is not a witch hunt, of course. But it is an independent source of information that threatens Trump. (In The Atlantic, David Frum dismantles Trump’s “collusion is not a crime” claims.)

Trump supporters hurled angry insults at a CNN reporter during a rally. Trump then retweeted his son Eric praising a video of the incident as “#Truth.” The tweet was accompanied by the headline, “WATCH: Supporters of President Trump Chant ‘CNN Sucks’ During Jim Acosta’s Live Spot at Florida Rally.” It’s all part of Trump’s effort to make any media coverage unfavorable to him seem false. (“This is the president whipping up hatred,” writes Vox’s Zack Beauchamp, “then expressing his satisfaction with how his supporters are acting on his messages.”)

Trump’s press secretary, Sarah Huckabee Sanders, continued the attack on the media by leveling an incendiary charge against it: She implied that the media helped cause 9/11 by reporting that Osama bin Laden used a satellite phone, which caused him to stop doing so and in turn made him harder to catch before 2001. “It’s bunk,” says Susan Hennessey of the Brookings Institution, that has “long been used to discredit media.”

Related: “Trump doesn’t want a free press; he wants free propaganda,” Charles Blow writes. Margaret Sullivan of The Washington Post writes about the QAnon conspiracy theory, another effort by Trump allies to spread falsehoods, and my colleague Michelle Goldberg’s piece on QAnon from April is worth revisiting.