When House Republicans voted on Monday night to release a memo, compiled by Rep. Devin Nunes, alleging anti-Trump bias at the FBI, they raised a very serious question for American democracy.

The question is not whether there was a plot against Trump at the FBI, as the Nunes memo reportedly alleges. There is no evidence for such a claim, and it doesn’t pass the smell test. The real question is this: Will the FBI and Justice Department remain semi-independent agencies that check the president’s authority — or will they be brought under President Donald Trump’s direct control?

“Trump is shockingly overt about believing that the problem here is that the FBI is staffed by loyalists to the wrong person,” says Julian Sanchez, an expert on the intelligence community at the libertarian Cato Institute. “He does, in fact, seem to think that the job of the DOJ, and the FBI, and the rest of the intelligence community is to protect the president and follow his orders — including going after his political enemies based on stuff he saw on Fox News, if that’s what he wants to do.”

The release of the memo seems designed to give Trump cover to act on these impulses. FBI agents almost certainly recognize this, and some will likely try to fight back by leaking damaging information on Trump and courting allies on Capitol Hill. What we’re heading for, after the memo’s actual release, is open war between Trump and the FBI.

The winner will be determined in part by how many influential Republicans in the House and Senate are willing to defend the FBI’s independence in the coming days and weeks. The early signs on that front — like House Speaker Paul Ryan calling for a “cleanse” of the FBI on Tuesday morning — aren’t exactly encouraging.

“We’re entering a dangerous period for the country,” says Ryan Goodman, a former Defense Department special counsel and editor of the national security legal blog Just Security.

War between Trump and the FBI is coming

From what’s been publicly reported about the Nunes memo, the key allegation in it is that the FBI abused its power when requesting a surveillance warrant on Trump foreign policy adviser Carter Page. The argument is that the warrant, submitted to a Foreign Intelligence Surveillance Act (FISA) court, relied on dubious information from the Trump-Russia dossier compiled by former British spy Christopher Steele — and that the judge was not informed about the actual source of the information.

Given the amount of work required to get a FISA warrant submitted and approved, this would require an anti-Trump conspiracy of truly massive levels. Former FBI special agent and current Yale Law professor Asha Rangappa lays out how improbable this would be in a post on Just Security:

The Nunes Memo reportedly alleges that at least a dozen FBI agents and DOJ prosecutors fabricated evidence, engaged in a criminal conspiracy to commit perjury, lucked out on being randomly assigned Judge Low Blood Sugar who looked the other way, and — coincidentally — ended up obtaining evidence that justified extending the initial FISA surveillance. ... If Nunes has in fact singlehandedly uncovered this vast criminal enterprise, it’s hard to know what’s more astonishing: That a government bureaucracy managed to pull it off — or that Nunes has exposed it all in a scant four-page memo.

What’s really important about the memo is whom it blames for all of this: Deputy Attorney General Rod Rosenstein. The memo, per a New York Times account, says that Rosenstein is the one who signed off on this sham FISA application.

Rosenstein is, after Attorney General Jeff Sessions’s recusal, the person supervising special counsel Robert Mueller’s Russia investigation. Trump can’t fire Mueller without Rosenstein’s say-so, and Rosenstein said in December that he sees no “good cause” to fire Mueller.

Rep. Nunes, the memo’s author, and the Republicans who have been most vocal in calling for its release, like Rep. Matt Gaetz, are also some of the Mueller investigation’s fiercest critics.

“The release of the memo, and the fabrication of a set of ideas around the memo, empowers Trump to go after the FBI,” Goodman says. “The ultimate goal is undermining the Mueller investigation. There doesn’t seem to be another reason for the president to be so obsessed with Rod Rosenstein and to be gunning for him.”

The FBI, historically, tends to resent efforts by the political branches to interfere with its internal workings. This is that, on a grand and extremely visible scale.

“The critical factor is the will of many Republicans to stand up”

FBI agents can fight back in a number of ways. Individual agents can leak classified information that looks bad for Trump, which has already happened throughout the Trump administration. The leak of proof to the Washington Post that then-National Security Adviser Michael Flynn was lying to about his contacts with Russians was, as far as we can tell, the key reason he was fired last February.

The FBI can also work with Democrats, and maybe some friendly Republicans, in Congress to try to discredit the Nunes memo or push through legislation protecting Mueller from being fired. Executive agencies work with friendly members of Congress all the time to protect their pet priorities; it’s hard to imagine this being an exception.

The problem, though, is that any attempt by the FBI to protect itself will only strengthen Trump’s resolve to attack it. FBI efforts to respond to a GOP attack on its independence look a lot like an FBI conspiracy against Trump, when viewed from a certain partisan angle.

“You don’t really want the FBI fighting back with all the means at its disposal,” Sanchez says, “because that would help validate what they [Trump and Republicans] are saying.”

The House vote to release the Nunes memo has kicked off an ugly cycle. The memo is now set to be released in the next five days, assuming the White House signs off. When it does come out, Trump, House Republicans, and influential conservative media outlets will talk loudly about how damaging it is. When the FBI pushes back against that, as it probably will in some way, Republicans will take that very pushback as further evidence of the need to “cleanse” the bureau, as Speaker Ryan put it.

The war between the GOP and the FBI is about to begin in earnest.

How does this end?

There are two broad ways this war could go. In the first, the FBI is brought to heel. Rosenstein and the other senior FBI executives are fired and replaced with more Trump-friendly appointees. The Mueller investigation is quashed, and the bureau essentially serves more like an arm of the Trump administration than a quasi-independent agency.

The implications of this scenario for American democracy are pretty scary.

“I shudder to think what the [2020] election looks like when you’ve got a guy who says, ‘I saw Fox & Friends this morning and my opponent is a crook’ ... except now you’ve got an FBI and a DOJ that say, ‘Yes, sir,’” says Sanchez.

In a second scenario, the memo leads to a lot of FBI-Republican skirmishing but no actual showdown. Trump either decides not to fire Rosenstein or is somehow stopped from doing so; the Mueller investigation continues unhampered, and the FBI remains relatively untainted by political influence.

There are many factors that could make the difference between these two outcomes. Two of the key ones are congressional Republicans, particularly Senate Republicans, and Trump’s own staff.

Senate Republicans have been notably quieter and more restrained about attacking the FBI than their peers in the House. Senate Republicans also have to confirm Trump appointees to the DOJ; they could make clear that if he fires Rosenstein/Mueller and tries to appoint a crony to take their place, they won’t confirm whomever he picks.

What influential Senate Republicans say and do now, in short, could signal to Trump whether he has enough backing to really take on the FBI.

“This particular president advances when he senses weakness,” Goodman says. “The critical factor is the will of many Republicans to stand up.”

Members of Trump’s White House have also blocked his moves to interfere with the FBI in the past.

The New York Times reports that in June, Trump ordered White House counsel Don McGahn to fire Mueller. McGahn said he’d rather resign than do that, and Trump backed down. He was, according to the Times, “concerned that firing the special counsel would incite more questions about whether the White House was trying to obstruct the Russia investigation.”

If McGahn and other voices of relative restraint in the White House succeed in backing the president away from the memo fever that will soon be playing out all over conservative news, or even outright refuse to carry out his orders, then you might see the same thing again in the wake of the memo’s release.

It’s far too early to say how the memo fight will ultimately be resolved — though in the past, American institutions have stood up pretty well against Trump’s more anti-democratic impulses. We’ll just have to wait and see.

But what’s clear right now is that the brewing battle between Trump and the FBI, regardless of how it plays out in terms of the bureau’s independence, isn’t good news for the American political system.

“I think the real depressing result here is the increased perception that both the law enforcement and intelligence agencies and their overseers are nothing more than partisan political playthings for the party in power,” Steve Vladeck, an expert on national security law at the University of Texas Austin, tells me. “It will do substantial long-term harm to our ability to believe that the government acts for legitimate reasons even when we disagree with what it’s doing.”