Silence is special counsel Robert Mueller’s most valuable tool, and he’s been wielding it to tremendous effect. The former FBI director has made no public statements and held no press conferences since taking over the Russia investigation last May. The pitter-patter of indictments and plea deals suggest something much larger may be at work, but nobody knows for sure, save for him and his apparently airtight team of investigators.

It’s a sharp prosecutorial strategy. He’s kept President Donald Trump, lawmakers from both parties, and the American public guessing about his ultimate conclusions and when he’ll reach them. But it also leaves a void in urgent debates about Russia’s meddling in the 2016 presidential election. Just how extensive were the Russian government’s efforts to exploit existing fissures in American society? Why didn’t the Obama administration do more to prevent or mitigate Russian interference while they were in progress?

One question looms above all others: Did Trump and his inner circle collude with Russia to undermine Hillary Clinton’s presidential bid? The president and his allies denounce any suggestion of collusion as a Democratic plot to invalidate the results of the 2016 election. Democrats are more certain that the answer is yes, although they don’t have proof of it yet.

Others are more circumspect, especially in the world of political journalism. Blake Hounshell, Politico Magazine’s editor-in-chief, staked out his position as a confessed “Russiagate skeptic” over the weekend. This isn’t the denialist perspective that blares from Fox News and other pro-Trump media outlets on a nightly basis. Hounshell is simply unconvinced by the publicly available evidence that Trump colluded with Russia. He cites the Trump campaign’s constant leaks, the president’s proclivity for boasting, and the dubious capacity for international intrigue of aides like George Papadopoulos and Carter Page.

“Mueller’s team doesn’t leak, and he’s repeatedly surprised us, as he did again on Friday,” Hounshell wrote, referring to the special counsel’s surprise indictment of thirteen Russians. “But I’m still waiting for a smoking gun—and the special counsel hasn’t shown us one yet, assuming he ever will.”

Vox’ Matt Yglesias responded with the perspective of a “Russiagate true believer.” If Hounshell believes there’s too much smoke and not enough fire, Yglesias thinks there’s too much smoke for there to not be a massive conflagration. “Trump–Russia skeptics, legion in the political press, brush all this aside in a gesture of faux sophistication, positing a bizarre series of coincidences complete with a massive cover-up all—for no particular reason,” he wrote.

Instead of a hapless fool, Yglesias argues, Trump’s business and political career to date “suggests a cunning, ruthless, and, in many ways, insightful man—not some kind of Forrest Gump-like figure ambling through history.” Yglesias points out that Paul Manafort, who managed Trump’s campaign for several months 2016, cut his political teeth on foreign electioneering in Ukraine for pro-Russian parties; and that Donald Trump Jr. is on the record welcoming the Russian government’s clandestine aid in undermining Clinton (“If it’s what you say I love it”). And he notes that Trump spent the entire campaign praising President Vladimir Putin and putting forth an incontestably pro-Russian foreign policy for no domestic political benefit.

“Perhaps this will prove wrong,” he wrote, “and ultimately the Mueller investigation will uncover nothing of note except crimes committed by Trump’s former national security adviser, his former campaign manager and deputy campaign manager, and a handful of lesser players while having also exposed both the president himself and essentially his entire senior staff as habitual liars on a manner of criminal and national security import.”

Yglesias isn’t alone in his confidence. The Intercept’s James Risen, a veteran reporter of the U.S. intelligence system, recently wrote that “it seems increasingly likely that the Russians have pulled off the most consequential covert action operation since Germany put Lenin on a train back to Petrograd in 1917.” Risen also criticized the political-journalism establishment for its skepticism about the seriousness of the Trump campaign’s wrongdoing:

Most pundits in Washington now recoil at any suggestion that the Trump-Russia story is really about treason. They all want to say it’s about something else—what, they aren’t quite sure. They are afraid to use serious words. They are in the business of breaking down the Trump-Russia narrative into a long series of bite-sized, incremental stories in which the gravity of the overall case often gets lost. They seem to think that treason is too much of a conversation-stopper, that it interrupts the flow of cable television and Twitter. God forbid you might upset the right wing! (And the left wing, for that matter.)

But if a presidential candidate or his lieutenants secretly work with a foreign government that is a longtime adversary of the United States to manipulate and then win a presidential election, that is almost a textbook definition of treason.

I wouldn’t quite put myself in either of these camps. First, there’s still plenty of room for reasonable doubt on whether Trump and his associates abetted Moscow’s meddling. Putin’s animus towards Clinton is well-established, as is Russian interference in European elections, so it’s not much of a surprise that Russia would try to undermine her candidacy. A true believer will be quick to note that damaging Clinton’s campaign is the best way to bolster Trump’s chances, but the reverse is also true. By the same token, Trump’s long, amicable history with Russian oligarchs may have been a conduit for clandestine dealings with the Kremlin—but it may also explain why he views the country far more favorably than the American foreign-policy establishment does.

Second, Trump’s personality and political inexperience complicate matters. His presidential campaign was a ragtag operation largely staffed by inexperienced family members and second-tier consultants. Trump’s disordered management style pits aides against one another and rewards reckless behavior. There’d be virtually no excuse if a more experienced and professional staff had welcomed the prospect of dirt on their opponent from a Russian lawyer or a mysterious professor in London. But sheer incompetence can’t be ruled out when it comes to the Trump campaign.

What pushes me closest towards Yglesias’ and Risen’s point of view is that all of Mueller’s moves so far—and many of Trump’s efforts to hinder him—make the most sense if the president thinks the special counsel can prove some kind of collusion. But what both journalists describe is also a good reason for caution before ruling out all other possibilities. If Trump struck a deal with Moscow to help win the election, it would be the worst political crisis in this country other than the Civil War. The consent of the governed that gives Trump the authority to sign legislation, pardon crimes, nominate judges, and wage wars would be tainted by a fraudulent act. He would still be the lawful president of the United States, of course, but his entire administration would be illegitimate in a way that no other presidency has even been.

The practical ramifications would then be far greater than anything experienced during the Watergate crisis, our closest historical parallel. Even Richard Nixon wasn’t the agent of a foreign power. Intelligence agencies would wonder whether they could trust the White House with the nation’s most closely guarded secrets. Military officers may question whether the commander-in-chief was acting on America’s behalf, or on Russia’s. Democratic governance depends on a basic level of trust and faith in one’s fellow citizens to function. Few things could be more corrosive to it than this.

This isn’t a conclusion that should be reached without convincing proof. What’s already known is enough to justify Mueller’s investigation and see it through to the end, wherever and whenever that may be. It’s not that the president deserves the benefit of the doubt; he lost that when he fired James Comey as FBI director. It’s that the potential damage is worth the caution.