There are those who argue that President Trump’s endless disparagement of the news media is harmless — perhaps a little extreme at times, but mostly just a lot of talk.

Sure, he throws around terms such as “enemy of the people,” claims that accurate reporting unflattering to him is “fake news” and gleefully insults individual reporters — especially women of color. True, he likes to threaten to use the powers of his office to interfere with the business concerns of media companies he does not favor or to punish their owners.

But, come on, what has he really done that’s so bad?

On Friday, the bottom dropped out of that argument.

The day began with the chilling arrest of a CNN crew in Minneapolis — two of whom were people of color — even as their cameras rolled. Omar Jimenez, Bill Kirkos and Leonel Mendez were simply doing their jobs, covering the protests sparked by the death of George Floyd, a black man, after a white Minneapolis policeman knelt on his neck for more than eight minutes.

And the day ended with the CNN headquarters in Atlanta being vandalized.

In between, all around the country, journalists were harassed — sometimes by police, sometimes by protesters.

Outside the White House, demonstrators went after Fox News journalists, chasing them out of Lafayette Square.

CNN President Jeff Zucker began a Saturday morning email to staff with an understatement: “It has been a long 24 hours.”

No doubt.

But the seeds of that long day were planted years ago: The press has been attacked and disparaged by politicians for decades, whenever they found it served their purposes to slap around the “nattering nabobs of negativism,” as Richard Nixon’s vice president, Spiro Agnew, once put it.

So no, Trump didn’t start this.

But he has made it immeasurably worse.

“By denigrating journalists so often, he has degraded respect for what journalists do and the crucial role they play in a democracy,” said Suzanne Nossel, chief executive of PEN America, the nonprofit organization devoted to free expression.

And, she told me, it’s working: “He’s been remarkably effective in contributing to this topsy-turvy sense that journalists are the opposition.”

Think of the campaign rallies where Trump egged on the crowds in raucous chants of “CNN sucks.” Or the many times — even in the midst of the coronavirus pandemic — when he has responded to respectful questions on matters of life and death by ripping into the inquiring reporters.

The goal of all this trash talk? Simple enough: to eat away at the press’s credibility. CBS reporter Lesley Stahl said Trump admitted as much to her shortly before the 2016 election:

“He said, ‘You know why I do it? I do it to discredit you all and demean you all, so when you write negative stories about me, no one will believe you.’ ”

This disrespect from the top has emboldened politicians at every level to falsely cry “fake news” when they don’t like a story. It has deepened the public distrust in the news media. It has even caused the United States to slip down in the international rankings of press rights.

“Trump tapped into hostility that was already there, and he has piled on and made it worse,” said Joel Simon, executive director of the Committee to Protect Journalists.

That hostility stemmed, at least in part, from a sense that the press is just another elite institution that many Americans are convinced doesn’t represent their interests or share their values.

Trump has urged them to hate the press — and apparently, many have heeded him. (Press critic and media scholar Jay Rosen of New York University has identified Trump’s “brand promise” to his base as essentially, “Watch, we will put these people down for you.”)

In recent months, journalists across the country have proved their worth daily with crucial reporting on the effects of the novel coronavirus on communities. They have done so relentlessly, even as many of their news organizations have been devastated by the economic downturn, and even as many of them have been laid off or furloughed.

And now, amid this new crisis, their colleagues are being arrested, tear-gassed and harassed at every turn.

It’s possible to imagine a leader who would have reacted to Friday’s attacks on journalists very differently.

“The president could have lowered the temperature by reminding people that journalists are essential to our democracy and deserve to be allowed to do their jobs,” Simon said.

That kind of message might have had a positive impact on mayors and governors, who in turn could affect the way police and protesters alike might respond when they see reporters at work gathering the news.

Instead, the president took a different tack: He celebrated CNN’s no good, very bad day by retweeting a nasty taunt about the vandalism at the Atlanta headquarters.

Far from helping to put out the anti-press flames, Trump instead got out his trusty gasoline can.

Not surprising, in the least. But still plenty shameful.

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