But the circle of people defending the president is getting smaller. Aside from his close family, there is no reason to doubt others might turn against him, should things get tough. It’s already happened, after all, with former White House advisor Steve Bannon and Michael Flynn, Trump’s initial pick for national security advisor.

This time it’s Cohen, with each leak offering further evidence of how misguided Trump is in choosing his closest collaborators.

This begins and ends with an issue of values: For Trump, personal loyalty is the most important trait when he picks his confidants. That’s a terrible metric.

Trump witnessed Cohen lie, and threat, and cheat for him. Evidently—understandably, even—he read that as a sign of dedication. Instead, he should have seen it for what it showed: that Cohen was capable of lying, threatening, cheating. He was Trump’s pitbull—and there was no reason to expect he wouldn’t turn to bite his owner.

There is a simple rule that applies to business deals, management, relationships—in short, life: Liars lie. Cheaters cheat. You don’t want someone who would do anything for you as a partner, an employee, or personal lawyer; you want someone who would do anything moral for you. Sure, it’s tempting to believe that someone who makes you an accomplice of their lies by confiding in you is somehow allowing you into a deeper circle of trust, but it’s not true.

What they are doing, instead, is showing you flawed morals and character—and those are people who shouldn’t be kept close, but at arm’s length.

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