“I don’t recall” is the two-foot putt of politics—a gimme. No one’s going to hassle you over it. It could be total bullshit and everybody knows it’s total bullshit, but if you say I can’t recall, nobody can really challenge it, so you get away with it, and sooner or later, usually sooner, the world moves on to other matters.

So GOP senators Tom Cotton and David Perdue could easily have left it at that. They didn’t recall President Trump saying “shithole,” which was their original position last week. The country would have rolled its collective eyes but granted them their gimme. But on Sunday, they decided the Republican Party hasn’t done enough sucking up to and lying for Donald Trump, so they went on the attack. Now, they said, Illinois Democrat Dick Durbin was lying. Trump never said “shithole.” Perhaps “shithouse.” Ah, well that’s different! As the Times put it, their “recollections appeared to have sharpened.”

I suspect that what actually “sharpened” were two things. First, their knowledge that they have this big immigration bill they sponsored together, called the RAISE Act, that would cut legal immigration roughly in half over 10 years, that they want Trump to sign. And second, their realization that they’re dealing with a man so fragile and vain that if they want him to stay interested in their bill, they’d better lie for him, because lying is what Trump demands.

The bill, as the Beast’s Jackie Kucinich and Andrew Desiderio reported last August when it was dropped, has almost no hope of passage. As they pointed out, it would need to clear the 60-vote hurdle in the Senate, which isn’t happening. All Democrats will likely oppose it. Even a handful of Senate Republicans are likely to be against it. Lindsey Graham came out against it immediately, and others made unsupportive noises.

But the bill is only part of the story. The other and more important part—maybe not more important to Cotton and Perdue, but certainly more important to the republic—is the way Trump keeps going lower and lower and lower, and the way Republican elected officials keep shoveling out his path for him.

No serious person can possibly think in all honesty Trump didn’t say the word. First of all, Trump was reportedly bragging about it to friends that night. Second, How likely would Durbin be to tell an outright lie about words spoken by the President of the United States? No matter how much he may dislike a president, a senator just doesn’t do that. (Or, at least they didn’t. What Cotton and Perdue are doing now is how confidence in offices and institutions gets depleted.) There were a lot of senators who disliked Barack Obama too, but no one ever came out of a White House meeting about rural policy charging that Obama made a remark about “shithole” states.

That’s mainly because Obama was too dignified ever to use that kind of language while conducting the people’s business, but it’s also because you just don’t tell lies about what presidents said. Lindsey Graham backed up Durbin last week, without exactly going as far as Durbin did. And just Monday, Graham restated his position, phrased as a sly little dig at Cotton and Perdue: “My memory hasn’t evolved,” he told a South Carolina newspaper. He added: “It’s pretty embarrassing when you have to take your children out of the room just to report the news.” I think we all know what he means.

Cotton and Perdue have relationships with Trump that are different, although at crunch time the differences don’t appear to be amounting to anything. Cotton, of course, is one of the biggest war hawks in Washington, who once said that a successful bombing campaign against Iran would take only “several days.” Aside from the hard line on Iran, he disagrees with Trump on a lot of things: He’s pro-NATO, pro-free trade, pro-Nafta, and was pro-Iraq war. Trump’s against all those things.

But he endorsed Trump anyway in May 2016, the same day John McCain did. When asked two months later by Atlantic editor Jeff Goldberg at the Aspen Ideas Festival (yes, Cotton is the kind of Republican who gets invited to the Aspen Ideas Festival) to square his worldview with his endorsement, Cotton of course was able to rationalize it. Trump’s views, Cotton said, aren’t as radical as they seem. And where President Trump seemed to be going off the rails, why, the Republicans in Congress would keep him in check, don’t you know. “If Donald Trump is elected president, I will support him when he is right and we’ll try to change [his] direction when he is wrong,” Cotton told Goldberg.

Perdue, who is not the kind of Republican who gets invited to the Aspen Ideas Festival, was a businessman before winning his Senate seat. His great claim to fame was running the Dollar Store and supplying America with thousands of jobs that pay about $17,000 a year. He has been cozier with Trump from the start. After Perdue won, Trump summoned him to Fifth Avenue and peppered him with questions about what it was like to run as a businessman-outsider. Perdue is now, by some accounts, Trump’s favorite senator. And he’s obviously determined to keep things that way.

Trump’s remark was an important symbolic low-point of his presidency. It resonated around the world. The outrages are so numerous that we can’t always know which ones will make the history books. We can be certain that this one will. A moment of national humiliation and disgrace.

Cotton and Perdue have chosen to go out of their way to align themselves with this humiliation. Their colleague Jeff Flake is giving a speech Wednesday comparing Trump to Stalin . Cotton and Perdue might well ask themselves what that makes them.