There were a variety of highly unfortunate moments during the Senate impeachment trial on Saturday, as Donald Trump's defense team began its opening arguments, but among the most unsettling came at the hands of Jay Sekulow, one of the president's controversial attorneys. NBC News reported:

"The House managers, over a 23-hour period, kept pushing this false dichotomy that it was either Russia or Ukraine, but not both," Sekulow said, attempting to suggest that Ukraine also interfered in the last presidential election as part of Trump's defense that his actions with respect to the country were proper and predicated on legitimate national security concerns. While this argument echoes the president -- Trump has repeatedly suggested that the 2016 meddling began in Ukraine while expressing skepticism about what the U.S. intelligence community concluded was a concerted and far-reaching effort by Russia to interfere in 2016 -- it's been previously debunked by numerous intelligence and government officials, including Trump appointees.

I'd hoped we were past this. The New York Times reported more than two months ago that American intelligence professionals had informed senators and their aides that Russia had engaged in a lengthy campaign "to essentially frame" Ukraine for Russia's 2016 election attack.

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The same week, Dr. Fiona Hill, the former top Russia expert on the White House National Security Council, reminded Congress that assertions about Ukraine targeting our elections represent a "false narrative" being "perpetrated and propagated by the Russian security services."

David Laufman, who served as the Justice Department's top counterintelligence official, wrote in November, "From this moment forward, any member of Congress or U.S. government official who persists in making this claim is, essentially, aiding and abetting the enemy."

And yet, an alarming number of Republicans -- including, evidently, a member of the president's legal defense team -- appear reluctant to let this go. Making matters slightly worse, Sen. Tom Cotton (R-Ark.) helped explain why so many in his party are indifferent to the warnings from their own country's intelligence community.

When asked by CBS' Margaret Brennan on whether he thinks it was a "misstep" for Trump lawyer Jay Sekulow to float the conspiracy theory that Ukraine meddled in the 2016 election on the Senate floor, Cotton replied "that's not a conspiracy theory.' Brennan then pointed out that Sen. John Thune (R-ND) -- one of Cotton's Republican colleagues -- said that he'd prefer for Trump's lawyers to not spread Ukraine conspiracy theories during the trial, which Cotton dismissed as "a Democratic talking point." After Brennan pointed out to Cotton again that Thune is a Republican leader who takes issue with Ukraine conspiracy theories being mentioned on the Senate floor, Cotton doubled down that the criticism is a "Democratic talking point."

The Arkansas Republican added that the "talking point" was that Team Trump peddled the Ukraine conspiracy theory that Sekulow appeared to reference on the Senate floor on Saturday.

We're occasionally reminded why Democrats and Republicans struggle to share a common reality.

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