The circular logic of those who think the dirty dossier is right about Trump

Byron York:

It's always important to understand how you know what you know, or what you think you know. It's particularly important in the case of the Trump dossier.

Consider the increasing number of claims that the incendiary allegations of the dossier "check out," in the words of New York Times columnist Bret Stephens.

Bankrolled by the Hillary Clinton campaign and the DNC, guided by the dirt-digging opposition research firm Fusion GPS, and compiled by the former British spy Christopher Steele, the dossier's key allegation is this: "There was a well-developed conspiracy of cooperation between [the Trump campaign] and the Russian leadership." Steele attributed that claim to "Source E," whom he described as "an ethnic Russian close associate of Republican presidential candidate Donald Trump."

"What's relevant is [Steele's] credibility, the reliability of his sources and the truthfulness of their claims," Stephens wrote recently. "These check out."

But do they? In reality, most reasonable people not named Mueller would have to say we don't know.

"As it relates to the Steele dossier, unfortunately the committee has hit a wall," Senate Intelligence Committee chairman Richard Burr noted last month. The committee's investigation, the best probe outside of the Mueller special prosecutor operation, has not even been able to discover who Steele's sources were, Burr said.
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Voila: Isikoff reported, accurately, U.S. intelligence agencies received intelligence reports on Page's trip. The alleged actions involving Page that Isikoff reported -- attributed to a "Western intelligence source," which was some reporters' shorthand for the former British spy -- lined up precisely with the contents of Steele's dossier. (Even John Sipher conceded that, "Admittedly, Isikoff's reporting may have relied on Steele himself for that information.")

Given all that, Stephens' point that the dossier "checks out" is basically saying the dossier proves the dossier.
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There is much more.

York gets to the heart of the arguments of supporters of the dossier and pretty much rebuts them based on the public knowledge about the dossier and its still unknown sources.