A bit more than a decade ago, President George W. Bush's press secretary, Scott McClellan, found his credibility in tatters after it became clear he had misled reporters about the leaking of the name of a CIA operative.
Even though he arguably had been set up by less-than-forthright White House aides, McClellan resigned some months later.
Why? Establishing trust between the White House press secretary and the reporters he or she works with every day is critical.
As former Bush speechwriter David Frum tweeted advice for the new White House press secretary, Sean Spicer: "The smart press secretary will remember: He is rationed one lie per career. Use it wisely."
"So why do it?" NBC's Chuck Todd asked, urgently, insistently, repeatedly on Sunday. Why send Spicer out there to pick a fight with the press in the first full day of the Trump administration? Why have him make so many easily disproved statements all at once?
Todd sought answers in vain on Sunday's Meet the Press from Kellyanne Conway, a senior adviser to President Trump. She suggested that the hostility from reporters may force her to rethink her relationship with the press.
Yes, Time magazine reporter Zeke Miller, serving as a pool reporter during a quick visit to the Oval Office, wrongly reported that a bust of Martin Luther King Jr. on display during the Obama administration had been removed; it hadn't.
Miller retracted the report and apologized publicly, saying his view of the bust had been obstructed. But Spicer and White House Chief of Staff Reince Priebus argued the incorrect report proved the media's intentional unfairness to Trump.
Conway called that bust bust fake news, as in an intentional hoax; by all available evidence, it wasn't. It appears to have been a reporter's mistake, and a sloppy one.
Would that government officials or Trump aides correct and apologize so promptly for their accelerating number of untrue statements.
Take it as a given that the new president doesn't have thin skin — he has no skin at all. Trump proved that once more in his own tirade against reporters at the CIA on Saturday.
Trump said journalists had falsely reported a schism between the president and his intelligence services, though Trump himself had earlier compared the agencies' behavior toward him to the policies of Nazi Germany.
And Trump, together with his aides, accused the media of understating crowd sizes, poll numbers and ratings for his inauguration — all to allegedly lessen his stature.
Many White Houses resemble an extension of their campaigns. This White House has to date made little rhetorical accommodation in the shift to governing. Trump labored to prove his crowds and ratings exceeded those for Obama and for Saturday's protest marches.
This singular campaign endures in office. And I think that accounts for the blasts at the press, even more than the lightning-quick reactions Trump brings to perceived slights.
In the White House as during the campaign, Trump and his top aides attacked the press, attacked dissenters and attacked facts. Each fundamentally serves as an underpinning of democracy. Each attack agitates journalists and delights his most ardent fans.
As Todd pointed out, Spicer's complaints were largely petty: They were about crowd sizes. Fox News Sunday host Chris Wallace called the White House's obsession with crowd sizes "ridiculous." But it put the press corps on notice in the most public way that the White House would treat it as an adversary — just as Trump did during the campaign.
It serves to rally his core supporters. It sows confusion among the reporting ranks, as many journalists were sent to fact-check such things as lawn mats and magnetometers. The Washington Post's Erik Wemple argued Sunday on CNN that the Trump strategy is to challenge the small assertions so that it can dispute huge exposés to undercut them.
The media cannot afford to overreact. They cannot get lost in the minutiae. And yet reporters also cannot let one falsehood after another fly past unimpeded — especially ones that clearly carry such importance inside the Oval Office.
McClellan lost his job amid a scandal that involved the invasion of Iraq, personally vouching that White House aides had not disclosed the name of a CIA agent married to a critic of intelligence used to justify the invasion. They had. Vice President Dick Cheney's former chief of staff was ultimately convicted of federal charges.
On Saturday, Spicer marched out to mislead reporters and the public about a topic of no real consequence. What he had to say wasn't plausible from the moment he opened his mouth. It was about the attack, not the substance.
CNN did not carry his remarks live, offering a detailed dissection of his misleading and untrue statements afterward. It's what real reporting looks like (and is a sharp contrast to the long, live broadcasts of Trump's primary rallies that helped fuel his nomination).
Conway, for her part, told NBC's Todd that Spicer was offering "alternative facts," though he did not make an argument based on other evidence but served up untrue information. Whether presidential delusions or strategic lies, these claims were made in the face of clear-cut, countervailing evidence.
But the real action is away from the assertions about crowd size and indeed away from the White House briefing room itself. The press, charged with helping the public make sense of those who govern, should pay close attention.