Devin Nunes, the top Republican on the House Intelligence Committee, said Thursday that the impeachment inquiry had “poisoned the minds of fanatics,” and he was absolutely right—but not quite in the way that he meant. His comments, aimed at Democrats, instead came across in the hearing as projection, a sad summation of the intellectual rot that has spread through his own party during the Trump age.

President Trump, his defenders, and the Republican Party writ large have increasingly tied themselves in tighter and tighter knots, piling one conspiracy theory atop another. There’s the “Russia Hoax,” the “Deep State,” the idea that US intelligence had an “insurance policy” to keep Trump from winning, the crazy notion that the cybersecurity firm Crowdstrike is somehow hiding the DNC’s server in Ukraine (an idea still being pushed by former representative Sean Duffy).

And then there are two other widely discredited Ukraine-focused conspiracy theories that Trump himself appears to believe: That Ukraine actually was responsible for the 2016 election attack carried out by Russian intelligence, and that somehow Joe Biden, Hunter Biden, and the Ukrainian company Burisma are wrapped up in some corrupt embrace worthy of criminal charges.

That’s before you even get to the anti-Semitic trope that somehow George Soros is pulling all the strings of the Deep State and the Democrats, an idea advanced by none other than Rudy Giuliani on ABC News in September. The man once hailed has "America's Mayor" has become so consumed by “internet nonsense” that he’s even promoted the idea that the DNC hacked itself in 2016 to frame Russia.

Each conspiracy theory has been debunked in turn—through court records, indictments, and evidence; through testimony under oath; through the official assessments of US and allied intelligence, and even through detailed bipartisan congressional reports in the House and Senate.

And yet they persist, each in turn earning shoutouts and name-checks in the impeachment hearing, a clear indication that Trump’s GOP has become increasingly divorced from reality, its collective brain rotted by years of elevating as its national voices a rotating series of hucksters, grifters, con artists, fraudsters, and masters of malarkey—most of them more interested in personal profit than democratic political institutions.

Today, these conspiracies are being advanced not from the fringes but by the secretary of state and the president himself. Betraying his profound misunderstanding of technology and facts, Trump has said, “I still ask the FBI, ‘Where is the server?’ How come the FBI never got the server from the DNC? Where is the server? I want to see the server. Let’s see what’s on the server.” These conspiracies have become mainstream Republican talking points, the key intellectual foundation for the party’s inability to recognize Trump’s behavior with regard to Ukraine for what it is: a gross abuse of presidential power, and anathema to US interests.

“I think what happens is, when we start to look at the facts, everybody has their impression of what truth is,” said Republican representative and Trump ally Mark Meadows this week, assuring the president's supporters that they can simply choose not to believe reality.

The GOP’s discordant claims and head-scratching moments, scattered through the hearings over the last two weeks, have left witnesses baffled. The deep tracks of the Deep State, tangential names like Alexandra Chalupa, have been lobbed from left field by the GOP inquisitors, seemingly ominous non sequiturs meant to imply presidential enemies operating in the shadows.

“I’m sorry, what’s the question?” Ambassador William Taylor, the head of the US embassy in Ukraine, asked after the GOP’s inquiring counsel stumped him with conspiracies about Ukraine’s role in the 2016 election.

As Democratic representative Denny Heck lamented in the closing minutes of Thursday’s hearing, “I feel like I’ve been treated to a Gatling gun fire of myth propagation over the last couple of weeks.”

There’s a real cost to our country and our democracy in the Republican approach of rapid-fire falsehoods. In her testimony Thursday, Fiona Hill—a Trump appointee herself—started her opening statement with a forceful indictment of the party’s approach: The GOP, rather than defending the nation from all enemies foreign and domestic, is doing Vladimir Putin’s work for him.

“Based on questions and statements I have heard, some of you on this committee appear to believe that Russia and its security services did not conduct a campaign against our country and that perhaps, somehow for some reason, Ukraine did. This is a fictional narrative that has been perpetrated and propagated by the Russian security services themselves,” Hill said. “I would ask that you please not promote politically driven falsehoods that so clearly advance Russian interests," she later added.