Russian President Vladimir Putin smiles during his July 16 press conference with U.S. President Donald Trump after their meeting in Helsinki, Finland. | Pablo Martinez Monsivais / AP

Trump has thwarted all attempts to embarrass him, to expose his lack of empathy, his disregard of human suffering or injustice, his bullying response to attacks on his sexual behavior, his weight, his limited vocabulary. How do you blackmail someone who seems so proud of being attacked? Can you really excuse it as just his rampant attraction to strongmen, like he wants to be?

Even the multiple bankruptcies and financial failures of so many of his deals and products don’t bother him, though there must be stuff in there that contradicts his public image, so extreme are his efforts to hide his tax returns. It just could be he doesn’t have as much money as he claims or doesn’t want us to know how deviously he got it. But some deep business secret? Seems unlikely. He’s proud of generating the curiosity. He thumbs his nose rather than cowers in fear of being exposed—in fact, his diehards regard such obstinacy as his virtue, and his refusal to back down as a strength they wouldn’t accept from anyone in their own lives.

His desire to fund a border wall rules over common-sense funding needs in health care, transportation, veterans services, the environment, and more. His rambling rallies have become so painful that even the television media no longer bothers to show them.

He shoots off his mouth and he can’t stop. His bullheaded approach to economics is taking America over a slowly crumbling cliff and still he thinks American history begins with him, despite worries that it may end with him.

So what could Putin have on him that justifies such refusal to confront the Russian president directly? He hasn’t even imposed the sanctions on Russia that Congress has universally voted. His aides have had to press him again and again on this issue. He sure looks like he has something to hide. But I don’t think it’s the pee tape or the like. The Trump we know would brazen it out and believes he has a public that will go along.

In just one bizarre week in July, after his Helsinki meeting in private with Putin, Trump was so bombarded with criticism from his aides and fellow Republicans that he started an apology tour. Yes, the president who never apologizes fumbled with how he said “would” when he meant “wouldn’t” and other nonsense that doesn’t hold up in context. Then it was on to other laughable face-saving moves to protect his reputation of never backing down.

But then he really doubled down, as is his wont. He invited Putin to visit him in the White House ahead of the November midterms, trying to pretend the first meeting went so well.

It was a deliberate poke in the eye of every Republican who counted on him to help them, not hurt them on the ballot. It was a defiant swipe at all the obvious reports of how poorly he did the first time.

What is going on?

It may be simple. Suppose Putin has concrete evidence that Trump didn’t win the presidency on his own in 2016.

Suppose he and Trump have an unspoken accommodation—I won’t tell on you if you don’t tell on me. Be friendly or look out!

Imagine that Putin has solid court-firm evidence of voters influenced, states shackled, officials bought, misdirection successfully executed, data that goes beyond algorithms into testimony and tapes. He may not want to reveal his bag of tricks, but Trump wouldn’t want that even more.

The corollary—a lot of U.S. citizens would love to see evidence like that to take themselves off a nasty mental hook of responsibility. So far we have all grumblingly accepted that the minority vote-getter won the contest, blaming the electoral college system. If evidence emerges from Putin or Robert Mueller that the collusion reached all the way to the top, Trump knows such a revelation would start a flood and even force Republicans in Congress to grow a spine.

This is the one thing Trump lives in mortal terror of—hard evidence that he didn’t win the presidency on his own dime. His opposition to the special prosecutor is totally about this. His claim that there was no collusion has already been dismantled by the probe. The only question remaining is how high up the collusion went. Putin knows. The hold no longer looks that mysterious.

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