Now the words that fall from Trump’s pursed lips or, often misspelled, onto his Twitter feed are trite or false or meaningless. He’s angry with Nordstrom, for heaven’s sake, because the department store chain dropped his daughter Ivanka’s clothing line! This is the concern of the leader of the free world.

Unpresidented!

I was struck by how Paul Horner, who runs a big Facebook fake-news operation, described our times in The Washington Post: “Honestly people are definitely dumber. They just keep passing stuff around. Nobody fact-checks anything anymore — I mean, that’s how Trump got elected. He just said whatever he wanted, and people believed everything, and when the things he said turned out not to be true, people didn’t care because they’d already accepted it. It’s real scary. I’ve never seen anything like it.”

We’ve never seen anything like it because when hundreds of millions of Americans are connected, anyone, clueless or not, can disseminate what they like with a click.

Horner came up, during the campaign, with the fake news story that a protester at a Trump rally had been paid $3,500. It went viral. We’ve had fake news accounts of how Hillary Clinton paid $62 million to Beyoncé and Jay Z to perform in Cleveland, and how Khizr Khan, the father of the Muslim American officer killed in Iraq, was an agent of the Muslim Brotherhood. Fake news — BREAKING! SHOCKING! — swayed the election.

Now we have President Trump suggesting that the real fake news is his negative polls — along with CNN, The New York Times, The Washington Post and any other news organizations that are doing their jobs: holding his authority to account and bearing witness to his acts. Stephen Bannon, Trump’s man of the shadows, thinks the media should “keep its mouth shut.” We won’t.

Sometimes I try to imagine what Trump’s Reichstag fire moment might be. In February 1933, a few weeks after Hitler became chancellor, fire engulfed the parliament in Berlin — an act of arson whose origin is still unclear. A recent New Yorker article by George Prochnik quoted the Austrian writer Stefan Zweig on Hitler’s savage reaction: “At one blow all of justice in Germany was smashed.”

From a president who loathes the press, who insults the judiciary, who has no time for American ideals of liberty or democracy, and whose predilection for violence is evident, what would be the reaction to a Reichstag fire in American guise — say a major act of terrorism?

We can only shudder at the thought.

Facts matter. The federal judiciary is pushing back. The administration is leaking. Journalism (no qualifier needed) has never been more important. Truth has not yet perished, but to deny that it is under siege would be to invite disaster.