Donald Trump’s accusation that a certain Fox News host is “really biased against me” has sparked a war between the Republican front-runner and the right-wing news channel that threatens to upend tonight’s debate. But it also shows how the real estate mogul’s controversial run for the presidency presents a fundamental challenge to journalistic objectivity. 

The idea of a disinterested media that tries to present neutral and factual reportage on all candidates is a relatively recent historical invention, and to some degree it operates on the premise that all the candidates work within the political system. Journalistic objectivity has a hard time dealing with unconventional candidates, and Trump’s defining characteristic as a politician is his willingness to thumb his nose at political conventions. Trump is habitually mendacious in a way that goes far beyond the normal deceptions of political rhetoric. He’s an unabashed xenophobe, and he’s willing to hurl personal abuse at any journalist who crosses his path, as in this sexist tweet: 

Given these traits, how is Trump to be covered as if he were simply another candidate like Jeb Bush or Hillary Clinton? 

Of course, for Fox News, the challenge of how to cover Trump presents a double bind. The network owes its success to the argument that it redresses the alleged liberal bias in the rest of the major media by offering a “fair and balanced” presentation of the news. Yet Trump has turned the logic of Fox News against itself, using the same rhetoric about media bias not against The New York Times or CNN but Fox. 

And with the growing recrimination between Fox and Trump, it’s hard not to take the side of the insurgent political candidate. Given the extremely hostile attacks Trump has received from the top brass of Fox News, the organization can fairly be said to be prejudiced against him. 

In a statement by Fox News given to Mediate, and seemingly written by network head Roger Ailes, Trump was openly mocked:

We learned from a secret back channel that the Ayatollah and Putin both intend to treat Donald Trump unfairly when they meet with him if he becomes president—a nefarious source tells us that Trump has his own secret plan to replace the Cabinet with his Twitter followers to see if he should even go to those meetings.

With its bluster and sarcasm, this statement was worthy of Trump himself, and not surprisingly the political candidate responded in kind with a statement from his campaign, which stated, “Unlike the very stupid, highly incompetent people running our country into the ground, Mr. Trump knows when to walk away. Roger Ailes and Fox News think they can toy with him, but Mr. Trump doesn’t play games.” Trump withdrew from the debate to run a rival event (although there is still the possibility that a last-minute deal will bring Trump back into the fold).

It’s easy to enjoy the Trump-Fox feud simply as political theater, but there is a genuine crisis here in journalistic objectivity. Journalists are supposed to report on a story from an impartial point of view, which is impossible with a candidate like Trump who insists on personalizing every exchange. In effect, Trump’s whole way of relating to the media is an attempt to make objective reporting impossible—which redounds to Trump’s benefit because it allows his supporters to reject all critical reports as “biased.”

While the war between Trump and Fox is especially intense, all other media outlets face the same problem. BuzzFeed Editor-in-Chief Ben Smith grappled with these issues in a letter to his staff in which he said it doesn’t violate the ideal of non-partisanship to say that Trump is a “mendacious racist.” Smith’s letter reflects a recognition of the reality that Trump is not like other candidates and demands a harsher characterization than most journalists usually apply to mainstream politicians. 

The real challenge BuzzFeed and other outlets will face is if Trump wins the Republican nomination. All the rules of American mainstream journalism dictate that Republican and Democratic presidential candidates be treated equally and as impartially as possible.

If Trump’s divisive politics forces the press to treat him differently than other candidates, this can often work to Trump’s advantage. Perhaps the deepest real bias the media has is towards sensationalism, and few politicians exploit that more cunningly than Trump.

Responding to a question about media bias against Trump, Jeb Bush, of all people, made a shrewd point, “He thinks he’s not being treated fairly. Really? Donald Trump’s not being treated fairly by the press? He consumes all the press! He’s a Stradivarius violinist from the Vienna Symphony” in his ability to play the press. 

Like much of the media, Fox News finds itself having to balance two competing impulses when covering Trump: his belligerence invites criticism, but it also draws an audience. If only for the high ratings he draws, Fox News might make amends with Trump for now—and start acting a little more fair and balanced.