(Erin Patrick O'Connor/The Washington Post)

No president has ever said what Donald Trump has said, let alone said it a day into his administration. “As you know,” he remarked Saturday, “I have a running war with the media.”

The president’s comment, made during a visit to CIA headquarters, seems to be news to the media, which hasn’t declared war back. But it does make explicit what has been obvious for months, if not years: Trump consolidated his public support in part by making journalists collectively into a political opponent. His frequent denunciations of the press as “lying” and reporters as “the most dishonest human beings on earth” have been a rallying cry for his supporters, as well as a shield for him against unfavorable reports about his statements, finances and personal behavior.

Now that he’s president, the stakes are higher than ever.

In office less than a week, Trump has insisted, despite evidence to the contrary, that attendance at his inauguration was the largest ever. He has asserted, on no proof at all, that between 3 million and 5 million people voted illegally in November. He then left it to his aides to sell both dubious claims. “It’s a belief he maintains,” press secretary Sean Spicer said, wanly, in response to questions about illegal voting.

Confronted by “Meet the Press” host Chuck Todd about Spicer’s wobbly defense of Trump, presidential adviser Kellyanne Conway coined an Orwellian rejoinder: Spicer possessed “alternative facts.”

Trump’s tactics in his war with the media bears some of the hallmarks of Stephen K. Bannon, his chief strategist and the former executive chairman of the “alt-right” site Breitbart News, said Kurt Bardella, Breitbart’s spokesman until last year.

“There is no question that Trump’s confrontational and combative tone towards the media is choreographed by Bannon,” said Bardella, a former congressional aide who heads a Washington communications firm. “It’s textbook Breitbart. If the facts aren’t on your side, attack the gatekeepers of the facts. . . . From Team Trump’s perspective, they won this way and have no rationale to change their winning playbook. Their objective will be to cast as much doubt as possible on traditional sources of information to ensure the environment is ripe for them to win in 2020.”

In fact, in an interview with the New York Times Wednesday evening, Bannon called the news media, not the Democratic Party, “the opposition party” of the Trump administration. “The media should be embarrassed and humiliated and keep its mouth shut and just listen for a while,” he said. He added, “The media here is the opposition party. They don’t understand this country.”

Trump’s war has a stark flip side: It’s rather one-sided. Few people in the news media would agree they’re at war with Trump. “We all know that in war the first casualty is the truth,” says Michael Oreskes, NPR’s senior vice president of news. “That’s not a loss we are prepared to suffer. We will do our work by our standards regardless of how the administration treats us. . . . The more the administration yells at us the calmer our presentation should be. We should avoid being baited into fights that seem to confirm the claim that we are at war.”

Nevertheless, journalists say they’ve had to recalibrate their approach to covering the president. For starters, there’s an active debate in some newsrooms, ongoing since the campaign, about how to describe the Trump administration’s more outrageous statements and assertions. Are they “falsehoods”? “Unsubstantiated” statements? Or “lies,” as the New York Times put it in a headline on Tuesday?

Former CBS anchor Dan Rather — whose reporting made him the bane of several presidents — put it forcefully in a widely shared Facebook post on Sunday: “What can we do?” he wrote. “We can all step up and say simply and without equivocation, ‘A lie, is a lie, is a lie!’ And if someone won’t say it, those of us who know that there is such a thing as the truth must do whatever is in our power to diminish the liar’s malignant reach into our society.”

But others suggest journalism doesn’t really need to change; it just has to be better.

“I think the most important response to the new president is to do our jobs, vigorously and fairly,” said Bill Keller, the former editor of the New York Times who now runs the Marshall Project, a nonprofit news organization focused on criminal justice. “But his tricky relationship with the truth calls for more than a lot of fact-checking. It bears close attention as a character trait with real consequences.”

Keller points out that Trump’s remarks about his “war” with the press were made at the CIA’s headquarters in Langley, Va. They included highly questionable statements about his inaugural crowd and the source of his “feud” with the intelligence community. Trump blamed the media for muddying his relationship with intelligence officials when, in fact, his own statements questioned their integrity.

“He was spouting obvious falsehoods to an audience for whom facts are matters of life and death,” Keller said. “The implicit, and truly dangerous, message to the intelligence community was ‘don’t bring me bad news; just tell me we’re winning.’ That’s scary.”

Like Keller, New Yorker magazine editor David Remnick marvels at the brazenness of Trump’s assertions, saying they set a tone comparable to Richard Nixon’s behavior in the White House.

“I think the journalistic response should, in the main, be journalism and more journalism: rigorous, deep, tireless and fearless,” Remnick said via email. “For a publication like ours, a point of view is fine, so long as it is supportable and the article is fair. What is not okay is to be partisan, to carry water for a cause and to overlook inconvenient facts.”

Added Remnick: “More real journalism is the answer. If that sounds righteous, so be it. The job, done at its best, has not changed. And when a lie is a lie — when you can discern willful inaccuracy, when you can discern deception and not merely error — we should call it what it is.”

The irony of Trump’s self-declared war with the media is that the media has already been a beneficiary of a fight it never picked.

Vanity Fair, for example, attracted a record 80,000 new subscriptions in the two weeks following Trump’s angry reaction to the magazine’s devastating review of a Trump-owned restaurant in Trump Tower. The New York Times got its own Trump Bump after he criticized the paper in a series of post-election tweets; in the first month after the election, the paper said it gained about 200,000 new digital and print subscribers, more than 10 times the number in the same period a year earlier, according to a spokeswoman. The three leading cable networks saw record audiences and profits, including CNN, which Trump has disparaged repeatedly.

Smaller, nonprofit news organizations such as the Marshall Project, ProPublica and Mother Jones magazine have seen increased donations. Keller said the election and Trump’s “hostility to criminal-justice reform” have attracted new donors to his site, which was founded in 2014.

The contributions were small, he said, but the intent was clear: “I think the election and the proliferation of fake news has prompted people to gather protectively around news sources they trust.”