So we now know that Trump lied to the American people about at least one part of his business relationship with Russia, a geopolitical foe that interfered in our election process on his behalf.

In a Jan. 11, 2017, news conference, Trump said that the “closest I came to Russia” was in selling a Palm Beach mansion to a Russian oligarch in 2008. While we’re just learning precisely how dishonest this was, Putin has known it all along. That means that throughout Trump’s campaign and presidency, Putin has had the power to plunge him into political crisis.

“If the Russians are aware that senior American officials are publicly stating things that are not true, it’s a counterintelligence nightmare,” Adam Schiff, the California Democrat in line to take over the House Intelligence Committee, told me.

As he points out, this issue contributed to former national security adviser Michael Flynn’s downfall. Flynn, you might remember, appeared to have lied to Vice President Mike Pence about his conversations with the Russian ambassador. This alarmed Sally Yates, then the acting attorney general, because the Russians would have known that Flynn was deceiving Pence, and could have used that knowledge against him. “Logic would tell you that you don’t want the national security adviser to be in a position where the Russians have leverage over him,” Yates told the Senate last year.

The same, said Schiff, “is true in spades for the president of the United States.”

Speaking to reporters before flying to Argentina on Thursday, Trump justified his pursuit of a Moscow project this way: “There was a good chance that I wouldn’t have won, in which case I would have gotten back into the business, and why should I lose lots of opportunities?” This could be read as a confession of motive. In the 2016 campaign, Russia wanted to humiliate Hillary Clinton and delegitimize America’s election. Trump wanted help building his brand.