A free press is under direct assault from the President of the United States, undermining one of the pillars of American democracy.
If Donald Trump succeeds in convincing a large number of Americans that major newspapers and television networks are illegitimate, then who knows how this will end.
Thursday morning's tweets were astonishingly vulgar, even for Donald Trump. They concerned Joe Scarborough and Mika Brzezinski, co-hosts of MSNBC's Morning Joe. The two had been making fun of Mr. Trump over a Washington Post story concerning highly flattering Time magazine covers featuring Mr. Trump that graced the walls of several of his properties. The magazine covers had been fabricated. (Talk about fake news.)
Mr. Trump was clearly exercised by the story. On Twitter, he accused the MSNBC hosts of trying to join him at his Mar-a-Lago estate at New Year's. "She was bleeding badly from a face-lift," he tweeted. "I said no!"
Mark Kornblau, NBC Universal News Group's senior vice-president of communications, replied by Twitter: "Never imagined a day when I would think to myself, 'It is beneath my dignity to respond to the President of the United States.' "
But White House deputy press secretary Sarah Huckabee Sanders was unapologetic. "He's not going to sit back and be attacked by the liberal media, Hollywood elites, and when they hit him he's going to hit back," she said at a White House press briefing Thursday afternoon.
But cyberbullying is the least of the President's recent offences. A far more pernicious series of tweets concerned a CNN report that linked a Russian investment fund to a former adviser to Mr. Trump. Not long after the story was published, the cable news channel's executives concluded it was insufficiently sourced. CNN withdrew the story and apologized. Three journalists who worked on the story resigned.
To be clear: The President of the United States publicly stated that three major television networks, one major cable news channel and two of the most respected newspapers in the United States are not legitimate news organizations.
The administration is matching words with actions by reducing the frequency of press briefings and banning television cameras from many of those briefings.
It led to a memorable flare-up earlier this week between Ms. Sanders and Brian Karem, who writes for several papers in the D.C. area and for Playboy.
Ms. Sanders had spoken for several minutes about what she considered irresponsible coverage of the Russia investigation, when she was interrupted by Mr. Karem.
"You're inflaming everybody right here, right now, with those words," he protested. Journalists who made mistakes suffered serious consequences, he told her, while the White House deliberately and routinely spreads disinformation.
"What you just did is inflammatory to people all over the country who look at it and say, 'See, once again, the President is right, and everybody out here is fake media,'" he continued. "And everybody in this room is only trying to do their job."
What's particularly disheartening about all of this is the reluctance of the conservative media to come to the defence of their own estate. In the past, print and broadcast organizations, whatever their ideological outlook, banded together to assert their right to investigate the administration of the day.
But not only are right-wing organizations such as Fox News, Breitbart and National Review dismissive of allegations of collusion between Russia and the Trump team, they themselves collude with the administration in accusing CNN and others of, as a National Review blog put it Thursday, "endemic absence of journalistic ethics and chronic malpractice." And they ignore or make light of the increasing restrictions placed on White House journalists covering the administration.
If some media are prepared to favour ideological affinity with an administration over their obligations as journalists to defend a free press, then the polarization of the American polity truly has become frightening.