The Isikoff piece publicly launched the Trump-Russia collusion narrative—only 1½ months from the election—and the whole dossier operation counts as one of the greatest political stitch-ups of all time. Most campaigns content themselves with planting oppo research with media sources. The Clinton campaign commissioned a foreign ex-spy to gin up rumors, which made it to U.S. intelligence agencies, and then got reporters to cite it as government-sourced. Mrs. Clinton now dismisses the dossier as routine oppo research, ignoring that her operation specifically engineered the contents to be referred to throughout the campaign as “intelligence” or a “government investigation.”

Making matters worse, there may be a grain of truth to that last claim. If the Washington Post’s reporting is correct, it was in the summer of 2016 that Jim Comey’s FBI obtained a wiretap warrant on Mr. Page from the Foreign Intelligence Surveillance Court. If it was the dossier that provoked that warrant, then the wrongs here are grave. Mr. Page is suing Yahoo News over that Isikoff story, but he may have a better case against the Clinton campaign and the federal government if they jointly spun a smear document into an abusive investigation.