On Wednesday afternoon, after the discovery of more suspected pipe bombs addressed to senior Democratic figures, President Trump called on Americans to “come together and send one very clear, strong, unmistakable message that acts or threats of political violence of any kind have no place in the United States of America.” Trump the Conciliator’s appearance on the national stage was a fleeting one. On Thursday morning, he returned to form, tweeting, “A very big part of the Anger we see today in our society is caused by the purposely false and inaccurate reporting of the Mainstream Media that I refer to as Fake News. It has gotten so bad and hateful that it is beyond description. Mainstream Media must clean up its act, FAST!”

Evidently, Trump and his aides were angry that some people in the media had had the temerity to point out the role that he has played in creating a political environment in which alarming incidents, such as the attempted pipe-bomb attacks, were increasingly likely. In a statement on Wednesday, Jeff Zucker, CNN’s president, said that Trump and his press secretary, Sarah Huckabee Sanders, “should understand their words matter. Thus far, they have shown no comprehension of that.”

On Thursday morning, speaking to Fox News, Sanders responded furiously to Zucker’s comments. She said that it was “absolutely disgraceful that one of the first public statements we heard from CNN yesterday was to put the blame and the responsibility of this despicable act on the President and on me personally, when the person who is responsible for this is the person who made and created and put these suspicious packages in the hands and in the arms of innocent American citizens.”

Part of what Sanders said was obviously true: the person responsible for these acts of terror is the bomber, who will, hopefully, be apprehended soon. But the rest of the White House’s response—including Trump’s tweet and Sanders’s interview—amounted to a depressing reminder that, even in a national emergency, with new suspicious packages seemingly being discovered by the hour, the President is incapable of acting as a unifying force for more than a few moments.

At the point of laboring the obvious, Zucker, whose offices were evacuated on Wednesday after the discovery of a suspicious package addressed to John Brennan, the former head of the C.I.A., care of CNN, had stopped well short of saying that Trump was directly responsible for the sending of the pipe bombs. In fact, Zucker had merely restated what A. G. Sulzberger, the publisher of the Times, told Trump face-to-face during a meeting at the White House this summer: that “his language was not just divisive but increasingly dangerous,” and that he needed to face up to this.

Whoever turns out to have sent the pipe bombs, the message that Zucker and Sulzberger delivered was eminently justified. Trump’s record of incitement doesn’t merely include targeting all the recipients of the suspicious packages on his Twitter account, and routinely using loaded phrases like “fake news” and “the enemy of the people” to describe journalists. During the 2016 election campaign, he encouraged attendees at his rallies to beat up protesters. Last July, he tweeted a mocked-up wrestling video of him body-slamming a man with a CNN logo superimposed across his face. Just last week, he praised Greg Gianforte, a Republican congressman who assaulted a reporter, calling him “my guy."

Trump’s defenders can and will claim that some of his incitements have been issued in a joking manner. That hardly matters. There is simply no precedent for a U.S. President using such inflammatory rhetoric, and launching such personalized attacks, on a nearly daily basis. And it isn’t just Democrats and members of the media who are pointing out that words can have consequences.

On Wednesday, David Gergen, the veteran Republican political commentator, who has worked for four different Presidents, said on CNN, “Donald Trump unleashed the dogs of hatred in this country from the day he declared he was running for President. And they’ve been snarling and barking at each other ever since. It’s just inevitable there are going to be acts of violence that grow out of that.”

The veteran Republican strategist Steve Schmidt, who worked on the Presidential campaigns of George W. Bush and John McCain, has become an ardent critic of Trump. On Wednesday, in a series of tweets commenting on the pipe-bomb attacks, he described Trump as “the greatest demagogue in American history,” someone who “has celebrated violence over and over again.” Schmidt went on, writing that “no journalist or commentator should be intimidated from making this point. The stoking of hatred and sundering of the American people was always going to lead to terrible consequences. Chief amongst them would be the initiation of partisan or sectarian violence within our country.”

It is hardly surprising that Trump got upset when he saw such statements. But, if he wants to prove his critics wrong, all he has to do is to stop vilifying journalists or anybody else who criticizes him and stick to the sort of placatory language that someone wrote for him on Wednesday. Instead, on Friday morning, he tweeted, “Funny how lowly rated CNN, and others, can criticize me at will, even blaming me for the current spate of Bombs and ridiculously comparing this to September 11th and the Oklahoma City bombing, yet when I criticize them they go wild and scream, ‘it’s just not Presidential!’ ” If he were ever going to start using the prerogatives of his office to bring Americans together rather than tearing them asunder, this was surely the occasion. But, there he was again, in the words of Greg Sargent, of the Washington Post, “blaming the media for an assassination attempt against it.” That’s who he is.