If you’re not a regular consumer of pro-Trump media outlets, it could be easy to underestimate or overlook the recent onslaught of attacks on Special Counsel Robert Mueller. There are a couple reasons for that. One is that this discourse exists almost entirely within that media ecosystem (which is distinct from, though overlapping with, the broader world of conservative media). The other is that critics have been calling for Mueller’s dismissal and an end to his probe since it was announced. Nonetheless, the intensity of the recent spree is notable, as is the gradual shift from ostensibly politically neutral critiques to openly partisan ones.

“Mueller is corrupt. The senior FBI is corrupt. The system is corrupt,” former House Speaker Newt Gingrich said on Fox News. The channel’s legal analyst Gregg Jarrett said Mueller was employing the FBI “just like the old KGB,” which Sean Hannity piously told viewers was “not hyperbole.” Using chilling language, Fox host Jeanine Pirro said, “There is a cleansing needed at the FBI and Department of Justice. It needs to be cleansed of individuals who should not just be fired but need to be taken out in handcuffs.”

Pirro is, not for the first time, moving way too fast. What all of these denunciations lack is any concrete instance of wrongdoing by a member of Mueller’s team, much less Mueller himself. They have seized on the case of FBI agent Peter Strzok, who apparently wrote some text messages critical of Trump to a girlfriend, but who, as I wrote last week, was immediately reassigned from Mueller’s team when Mueller learned of the texts, and about whom there is as yet no proof of wrongdoing. But the path from Mueller’s appointment to the current critiques bears close examination.

When Deputy Attorney General Rod Rosenstein appointed Mueller in May, the announcement drew varied conservative reactions. For some people, the special counsel’s probe was unnecessary, a validation of a preposterous conspiracy theory about Donald Trump’s presidential campaign colluding with Russia. Others argued that the appointment of a special counsel was constitutionally dubious. But some Trump backers welcomed Mueller’s appointment, seeing the former FBI director as a man of integrity who would finally clear the president. Newt Gingrich was one notable example:

Gingrich was right about Mueller’s reputation in Washington: He was a celebrated former FBI director, a longtime Republican, and an appointee of both Democratic and Republican presidents. And Rosenstein, who appointed him, was another example of a lifelong Republican, appointed by Trump, who had an impeccable reputation for fairness. (Incredibly, Trump would later disclaim Rosenstein and suggest he was a Democrat.) In an environment of hyper-polarization, Mueller seemed to be one of the few people in D.C. who had the gravitas and reputation to satisfy both sides.

In hindsight, this was hopelessly naive. Trump’s black-hole-like gravity is such that it overwhelms even reputations for probity and impartiality built up over decades. Not for everyone—many people retain their previous impression of Mueller—but another group quickly jettisoned it. That group is not defined ideologically—in no meaningful way is there a specifically and broadly held small-c conservative critique of Mueller. (Almost no one is still questioning the authority to appoint him.) Nor is there really a universally Republican critique of the probe. Senator Chuck Grassley, for example, is demanding answers about Strzok while also saying Mueller’s probe should be allowed to do its work.

The opposition to Mueller is partisan, but not in that it pits Republicans against Democrats. Its partisans are loyal first and foremost to President Trump. And in the inexorable logic of fiercely loyal partisans, they can only interpret other people’s actions through the same lens. Hence they have decided that Mueller, despite no real evidence in favor of the proposition and plenty of circumstantial evidence against it, must also be entirely partisan. (The same partisan impulse is at work in support for Roy Moore in the U.S. Senate race in Alabama.)

Gone by the wayside are some of the earlier critiques. Back in May, when Mueller started his work, Trump partisans could still argue with a straight face that there was no collusion between the Trump campaign and Russia, there was no evidence of collusion, and there would never be any evidence of collusion. Even if it eventually emerges that there was no criminal act involving collusion, it has become impossible to claim that the special counsel’s probe is purely a fishing expedition. The July revelation of a June 2016 meeting at Trump Tower with a Russian lawyer established that if there was no collusion, it was not for want of trying. Trump and others abandoned the talking point that there was no collusion and adopted a new one: Collusion is totally normal and appropriate! George Papadopoulos and Michael Flynn have since both pleaded guilty to lying about their contacts with Russian officials—in the former case, contacts that occurred during the campaign. Carter Page testified to the House about extensive contacts with Russians.

Another claim was that it was unnecessary and improper for Mueller to examine any issues outside the scope of the campaign, even though Mueller’s probe empowers him to investigate pretty much any crime he happens across in his work. Trump told The New York Times that if Mueller began probing his own finances, that would constitute a “red line,” implying (though never explicitly averring) that it would constitute grounds for firing. Yet since Mueller’s extensive indictment of Paul Manafort and Rick Gates, accusing them of laundering $75 million in foreign income, it has been harder to sustain the claim that there might not be serious crimes outside the campaign. Trump, too, has thought better of publicly repeating that he’d fire Mueller for poking into the Trump Organization or his personal finances, though that doesn’t mean he’s abandoned the idea.

Trump’s defenders have regrouped around the argument that the probe is a partisan effort to get Trump. This has long been the subtext of their attacks on the special counsel, but initially they clothed it in concerns about fairness or procedure or scope. Now, they are willing to state the stakes more bluntly: “Mueller poses an existential threat to the Trump presidency,” Newsmax CEO and Trump friend Chris Ruddy contends.

They are also seeking to discredit Mueller. Take Gingrich. Less than a month after praising Mueller as incorruptible, he was blasting him, saying that “Republicans are delusional if they think the special counsel is going to be fair” and calling on Congress to shut down the probe.

What drove Gingrich’s flip? He complained that some of the people who Mueller had hired had given to Democrats in the past. This is true, but is also clearly allowed within Department of Justice guidelines; ignores the fact that Mueller is the head of the investigation; and, as George Stephanopoulos noted, has been true of previous special prosecutors—like Republican donor Ken Starr, whose investigation of Bill Clinton Gingrich supported. Faced with that contradiction, Gingrich claimed that “we’re in a different world” today. Indeed we are: Today, Gingrich is an ally of the president who’s being investigated. As Gingrich well knows, it is not as if the late 1990s were an era of bipartisan comity. Though he presents his objections today as principled, Gingrich’s reversal, and current labeling of Mueller as “corrupt,” are probably best viewed in the context of his many comically opportunistic reversals over the years.

Nonetheless, the argument that Gingrich is making, whether sincere or not, bears examination. It allows Trump partisans to discredit the Mueller probe without having to prove that there was any wrongdoing or violation of protocols and rules—that is, without even having to establish that anyone’s supposed biases influenced any results of the probe.

They have raised the Strzok case, which doesn’t really reflect much about Mueller at all, and in any case also does not feature any proven wrongdoing in the course of Strzok’s job. The strongest argument against Mueller is his friendship with James Comey. The problem is that given Comey’s experience as both FBI director and deputy attorney general, there is practically no qualified lawyer with government experience who isn’t connected to Comey in some way. As I wrote last week, concurring with arch-conservative Andrew McCarthy, the U.S. governmental system is constructed on the idea that politically interested individuals can set aside their biases to serve in government roles, with sufficient guidelines and checks and balances.

The critique of the Mueller probe throws that concept out, asserting that everyone must be fanatically and foremost partisan, and that people can be thrown off the job without having to demonstrate wrongdoing. It far exceeds the demands of even a strong conflict-of-interest policy, and rejects the value of expertise and experience in favor of an illusory neutrality. This resembles similar right-wing critiques of academia and the press, and it is essentially nihilistic, seeking to disqualify not only avowed partisans but also those like Mueller, whose reputation Gingrich could praise heartily in May, denigrate in June, and call corrupt by December. The very idea of a reputation for fairness is obsolete before this totalizing partisanship. It doesn’t matter that Rosenstein last week rated Mueller’s work so far highly; as another lifelong Republican with a reputation for fairness, he can just as easily be written off, as Trump’s attack on him demonstrated.

The logic of Gingrich and Co. would produce the hollowing out of all non-elected precincts of the government—no agency, bureau, or department can withstand this test, as demonstrated by the fact that Trump partisans have taken to portraying the FBI, long a stronghold of conservatism and more recently a stronghold of pro-Trump feeling, as a hotbed of arch-liberal deep-state conspiracy. (It’s perhaps not a coincidence that as speaker, Gingrich worked to gut Congress’s nonpartisan and professional research staff, making the body dependent on lobbyists for information.)

Thus the cynicism of The Wall Street Journal editorial board’s conclusion that “Mr. Mueller is too conflicted to investigate the FBI and should step down in favor of someone more credible.” This, of course, was just who Robert Mueller was said to be a few short months ago. Even if Rosenstein could find a replacement with a reputation as strong as Mueller’s, it’s clear that the Trump partisans would just as quickly work to undermine it. Who would satisfy the Journal’s editors? It’s hard to imagine many names beyond, say, Pirro or her Fox colleague Andrew Napolitano, both of them unshakeable Trump partisans. Appointing such a person would finally satisfy those critics, but it would also effectively end the special counsel’s investigation—which is, of course, the point.