If House Intelligence Committee Republicans had been content to find no proof that Donald Trump’s presidential campaign conspired with Russia, it would have been up to partisans to argue about whether they looked hard enough. By departing even further from the facts to deny that Russia was rooting for Trump, the lawmakers all but confessed to a whitewash.

The Republicans’ conclusion this week that there was no collusion by the campaign was premature, and the question of the Trump team’s role remains unsettled — hence the continuing investigations by the Senate Intelligence Committee and special counsel. The Russian effort to boost Trump, on the other hand, is well established.

U.S. intelligence agencies concluded with “high confidence” last year that “Russian President Vladimir Putin ordered an influence campaign in 2016 aimed at the U.S. presidential election” and “developed a clear preference for President-elect Trump.” Committee Republicans’ divergence from that is so dubious that some of them have backpedaled by acknowledging that Russia aimed to hurt Hillary Clinton — as if that were somehow different from helping Trump.

Like the interference-running antics of Rep. Devin Nunes, the Central Valley Republican who chairs the panel but was forced to bow out of the investigation, the committee’s conclusion abets Trump’s denial of Russian aggression against America and its allies. This week, the White House hesitated to identify Moscow as a suspected party in the poisoning of a former spy in England. That was in sharp contrast to British Prime Minister Theresa May and Secretary of State Rex Tillerson, who was fired shortly after he seconded May’s determination that Russia was likely to blame.

Trump’s presidency poses a challenge to all manner of American institutions. The GOP-led House Intelligence Committee has categorically failed the test.

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