Politicians keep reminding us not to lose sight of special counsel Robert Mueller’s broader assignment: to investigate Russia’s interference in the 2016 election. If only someone had reminded Mueller.

One of the biggest failures of the Mueller probe concerns not what was in the final report, but what was not. Close readers will search in vain for any analysis of the central document in this affair: the infamous “dossier.” It’s a stunning omission, given the possibility that the Russians used that collection of reports to feed disinformation to U.S. intelligence agencies, sparking years of political maelstrom.

KIMBERLEY STRASSEL: MUELLER’S REPORT SPEAKS VOLUMES

The dossier -- compiled by former British spy Christopher Steele on behalf of Fusion GPS, an opposition-research firm working for the Hillary Clinton campaign and the Democratic National Committee -- fed to the Federal Bureau of Investigation and the media the principal allegations of the “collusion” narrative. It claimed Paul Manafort was at the center of a “well-developed” Trump-Russia “conspiracy”; that Carter Page served as his intermediary, conducting secret meetings with a Kremlin official and the head of a state energy company; that Michael Cohen held a clandestine meeting in Prague with Vladimir Putin cronies; and that the Russians had compromising material on Donald Trump, making him vulnerable to blackmail. The dossier was clearly important to the FBI probe. Its wild claims made up a significant section of the FBI’s application for a secret surveillance warrant on Page.

The Mueller report exposes the dossier claims as pure fiction. Yet in describing the actions of the Trump campaign figures the FBI accused, the report assiduously avoids any mention of the dossier or its allegations. Mueller refers to Steele and his work largely in passing, as part of the report’s description of how former FBI Director James Comey informed Trump of the dossier’s existence. The dossier is blandly described several times as “unverified allegations compiled” by Steele.

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