The Editorial Board

USA TODAY

Americans might soon learn what, if anything, special counsel Robert Mueller has found out about potential collusion between Donald Trump's presidential campaign and Russia.

But there's one Trump-Moscow link where the emerging evidence is already as damning as it is disturbing.

During much, if not all, of Trump's campaign he sought to enrich himself by pursuing a luxury hotel-condominium-office deal in Russia known as Trump Tower Moscow.

And as a candidate, Trump repeatedly misled or lied to voters about his business with Russia. "I have nothing to do with Russia," he told reporters in July 2016. "I don't deal there," he said during the Oct. 9 presidential debate.

OTHER VIEWS:' ‘We still have no evidence of collusion’

The truth is, Trump had coveted a lucrative hotel project in Russia — whether to build one or license his name to be emblazoned on a skyscraper — for decades. "We will be in Moscow at some point," he said in a 2007 deposition.

Later, as a presidential candidate, he secretly signed an 18-page letter of intent for Trump Tower Moscow on Oct. 28, 2015, the day of the third Republican presidential debate.

Court filings by Mueller in November make clear that negotiations led by Trump lawyer Michael Cohen continued through at least June 2016. Cohen lied about this to Congress to "give the false impression that the Moscow Project ended before 'the Iowa caucus and ... the very first primary,' " according to the filings.

You have to wonder what the fallout would have been if those negotiations had been exposed before Trump debated his Republican primary opponents or Hillary Clinton. The electorate certainly was robbed of knowing about this crucial information at a time when:

►There were news reports that Russia was interfering in the election.

►Trump was expressing praise and admiration for President Vladimir Putin, even as he was insulting hundreds of other people, places and things on Twitter.

►The candidate said that, as president, he would consider easing sanctions placed against Russia for its violent seizure of Crimea.

►Trump was questioning America's continued role in NATO, a bulwark against Russian aggression that Putin has historically despised.

►A plank in the GOP platform regarding U.S. support for Ukraine was watered down.

►Trump challenged Moscow to release Democratic emails that Russians were reported to have hacked.

How does the president explain the appearance of a quid pro quo? By claiming that he was just keeping his options open. "There was a good chance that I wouldn't have won," Trump said in November, "in which case I would have gotten back into the (real estate development) business. And why should I lose lots of opportunities?"

Exactly when the Trump Tower Moscow "opportunity" collapsed remains murky. On Sunday, the president's current lawyer, Rudy Giuliani, quoted Trump as telling him that project talks were "going on from the day I announced to the day I won." By Monday, Giuliani was scrambling to walk back his comments to The New York Times and other news outlets.

But whether Trump was pursuing the arrangement until he clinched the Republican nomination, or right up until he was elected president, isn't the main point. What matters is that a presidential candidate was secretly negotiating a major business deal with a major U.S. adversary — an extraordinary conflict of interest that was concealed from voters.

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