A blockbuster scoop in the New York Times reports that two White House officials helped House Intelligence Committee Chair Devin Nunes access intelligence reports showing that President Donald Trump and his associates were subject to “incidental collection” as U.S. intelligence agencies conducted routine foreign surveillance.

This is significant, because it shows Nunes may have had White House help in his ham-handed efforts to buttress (sort of) Trump’s false claim that former President Obama wiretapped his phones, and later, after admitting that didn’t happen, that Trump and associates were subject to U.S. surveillance. Nunes apparently cited the info he’d been given to suggest that Trump may have been wiretapped, though he later backed off of that assertion. If the White House provided that info, it adds to the case that Nunes is functioning as a defender of Trump rather than exercising oversight, by running his committee’s probe into Russian meddling and possible collusion between Russia and the Trump campaign.

Meanwhile, another big story is unfolding: Republicans on the Senate Intelligence Committee, which is running its own probe, are beginning to treat this matter with the seriousness it demands — particularly since it is now becoming apparent that the House probe is devolving into absurdity.

Indeed, a Senate Intel Committee hearing Thursday on Russian interference revealed some genuinely new — and stunning — information. It should worry Republicans just as much as Democrats — particularly the Republicans who continue to back Trump and Nunes.

Here’s what happened. In a remarkable moment, one key witness, Clinton Watts, a senior fellow at the George Washington Center for Cyber and Homeland Security, bluntly informed Sen. Marco Rubio, who serves on the Intelligence Committee, that as one of Trump’s presidential primary opponents, Rubio “suffered from” Russian disinformation efforts. (Although Watts wasn’t specific about those efforts, later in the day Rubio charged that Russian hackers have conducted unsuccessful cyber attacks on his former presidential campaign staffers.)

According to Watts (who was backed up by other witnesses who testified), the Russians have been using “active measures,” which are built on propaganda tactics that date back to Soviet times, to spread disinformation, fear, confusion, and chaos in multiple democratic countries, including the United States.

These efforts include the use of visible Kremlin propaganda outlets, such as RT and Sputnik, to publish false news stories and conspiracy theories. Russian actors then deploy social media bots to spread these false stories far and wide. In the U.S., Watts said, the goal has been to provoke the Trump into repeating them or retweeting them to his millions of followers.

In a moment that stunned the hearing room, Watts flatly stated that the president himself has become a cog in such Russian measures. When asked by Oklahoma Republican James Lankford, who appeared visibly dismayed, why, if Russians have long used these methods, they finally worked in this election cycle, Watts’ answer was extraordinary.

“I think this answer is very simple and is one no one is really saying in this room,” he said. Part of the reason, he went on, “is the commander in chief has used Russian active measures at times against his opponents.”

To buttress the claim that Trump (unwittingly or not) aided Russian disinformation efforts, Watts cited several instances. Among them: Trump’s citation of an apparently false Sputnik story at an October 2016 campaign appearance; his ongoing denial before and after the campaign of U.S. intelligence of Russian interference in the election; his claims of voter fraud and election rigging, which Watts said was pushed by RT and Sputnik; and Trump’s questioning of the citizenship of former President Barack Obama and even his primary rival Ted Cruz.

Watts added that one of the reasons such tactics are working is that Trump and/or his surrogates have repeated some of the claims, further spreading them through social media accounts that are owned both by real people and bots. Thus, the disinformation is kept alive and gradually becomes more real and plausible. “Part of the reason active measures work is because they parrot the same lines,” Watts said.

Republicans on the committee Thursday seemed to be grappling with the enormity of what this could mean — and, crucially, that this threat should not be seen through a partisan prism. Rubio questioned Watts about a series of such false news stories and hoaxes, including claims that a thousand Muslims had burned down the oldest church in Germany while shouting “Allahu Akbar,” that migrants had raped a German girl, and that the European Union planned to ban snowmen as racist. (If you’ve ever spent time on alt-right social media, there’s a familiar ring to these stories: they are exactly the sort of thing that gets spread and recycled, and reverberate as supposed evidence of the nefariousness of say, Muslims, or the overreach of “political correctness.”)

Rubio seemed to suggest that he sees these tactics as intended to divide Americans from one another. “Aren’t we in the midst of a blitzkrieg, for lack of a better term, of informational warfare conducted by Russian trolls, under the command of Vladimir Putin,” Rubio asked, that is designed to divide Americans “politically, socioeconomically, demographically, and the like?” Watts confirmed that one of the aims of Russian active measures is to “play on ethnic divisions.”

It’s not clear yet how much significance these revelations have, if any, to the ongoing probe into possible Russian-Trump campaign collusion. But the gravity of Thursday’s hearing — combined with the New York Times revelations — may prod Senate Republicans into stepping up, particularly to fill the vacuum caused by Nunes’ plummeting credibility.

Sarah Posner is a reporter and the author of “God’s Profits: Faith, Fraud, and the Republican Crusade for Values Voters.” Her work has appeared in The Washington Post, the New York Times, Rolling Stone, Mother Jones and many other publications.