Opinion writer

President Trump has an extraordinary ability to persuade his supporters to upend their prior beliefs about a whole range of questions. If you had said five or 10 years ago that in 2018 being a Republican in good standing would mean insisting that Vladimir Putin is our friend, NATO is nothing more than a nuisance, trade wars are glorious, the FBI is a nest of villainous hoodlums, and paying off a porn star and model to keep their mouths shut is just something a successful man has to do from time to time, no one would have believed you.

Today, the president is testing the limits of his supporters’ moral flexibility yet again. Simply put, he has never sounded more like a mafioso than he did in an interview with Fox News on Thursday, reacting to a question about why Michael Cohen had turned on him:

Because he makes a better deal when he uses me, like everybody else. And one of the reasons I respect Paul Manafort so much is he went through that trial, you know they make up stories, people make up stories. This whole thing about “flipping,” they call it. I know all about flipping, for 30, 40 years I’ve been watching flippers. Everything is wonderful, and then they get 10 years in jail and they flip on whoever the next highest one is or as high as you can go. It almost ought to be outlawed. It’s not fair. …

If somebody defrauded a bank and he is going to get 10 years in jail or 20 years in jail but if you can say something bad about Donald Trump and you will go down to two years or three years, which is the deal [Cohen] made, in all fairness to him, most people are going to do that. And I’ve seen it many times, I’ve had many friends involved in this stuff, it’s called “flipping” and it almost ought to be illegal.

All the outrageous and appalling things you’ve heard Trump say shouldn’t keep you from being shocked at this. First, note that Trump says, “I’ve had many friends involved in this stuff” — “this stuff” meaning being accused of a crime and being offered leniency in exchange for cooperating with law enforcement to help them secure convictions on more significant criminals. I don’t know about you, but I certainly don’t have many friends involved in that stuff, because I haven’t spent “30, 40 years” associating with apparent criminals.

Even more important, this technique — turning someone accused of a crime into a cooperating witness — happens every day in police stations and prosecutors’ offices around the country. It can certainly be abused, but it’s also the way law enforcement takes down drug gangs, organized crime, insider trading and plenty of other kinds of criminal conspiracies.

Yet Trump says that offering a suspect leniency in exchange for his testimony against others “almost ought to be illegal.” It’s the kind of thing you expect to hear from John Gotti, not the president of the United States.

But perhaps this shouldn’t be a surprise, knowing not only Trump’s history but also what he has been saying lately. After reporting revealed that White House counsel Donald McGahn has had extensive discussions with special counsel Robert S. Mueller III’s team, Trump on Sunday tweeted, “The failing @nytimes wrote a Fake piece today implying that because White House Councel [sic] Don McGahn was giving hours of testimony to the Special Councel [sic], he must be a John Dean type ‘RAT.’ ” John Dean, you’ll recall, publicly revealed many of  the misdeeds that made up Watergate, the worst scandal in American political history. To consider him not a hero but a “RAT,” you’d have to believe that he should have kept his mouth shut and let the crimes continue.

But Trump is big on people keeping their mouths shut. As head of the Trump Organization, as a candidate and as president, he has forced underlings to sign nondisclosure agreements forbidding them from revealing what saw while in his employ. In many cases, those agreements included non-disparagement clauses in which the signer had to pledge never to criticize Trump or his family for as long as they lived. The mafia had “omerta,” and Trump has the NDA.

So how will Republicans react to Trump’s diatribe against flipping criminals? Will they try to ignore it or decide he has a point?

The thing about a cult of personality is that its character depends on the personality in question. Republicans sometimes mocked Democrats for worshiping Barack Obama, and you might argue that some of his supporters got a bit starry-eyed at times, particularly in 2008. But Obama never asked them to suddenly offer a full-throated defense of something morally abhorrent simply because the president thought it might be good for him. Whether you agreed with his policy choices, Obama was a man of great personal integrity who ran an administration free of any significant scandal. No Obama supporter ever said, “Oh my god, I never thought he’d ask me to justify that.”

Trump does, on an almost daily basis. But if his supporters are having any doubts, they might want to consider that this won’t be the last time he asks them to abandon their principles.