The Steel Dossier wasn't what was fake - the Russian claims against Trump were fake, but they were really claimed by Russians, and the Dossier documented it, so that wasn't fake.
Just like you are real even though you make false claims. No one should say Hashi is a fake poster.
It was of interest to the FBI because, despite the Russian claims against Trump being fake, they could still really be used as leverage, and that's not fake either.
Anyway, just for the record:
Wikipedia wrote:Some aspects of the dossier have been corroborated,[29][30] in particular its main allegations that Putin and Russia actively favored Trump over Clinton[31][23] and that many Trump campaign officials and associates had multiple secret contacts with Russians.[32][33]
[...] According to Simpson's testimony, Steele, who enjoyed a good working reputation "for the knowledge he had developed over nearly 20 years working on Russia-related issues for British intelligence,[82] approached the FBI because he was concerned that Trump, then a candidate, was being blackmailed by Russia,[83] and he became "very concerned about whether this represented a national security threat".[23] Steele believed the intelligence community "needed urgently to know—if it didn't already—that the next possible U.S. president was potentially under the sway of Russia."[84]
[...] Contrary to a conspiracy theory[36][37] promoted by Trump,[38] Fox News,[39] and many of Trump's congressional supporters, the dossier was not the trigger for the opening of the FBI's "Crossfire Hurricane" counterintelligence investigation into "whether individuals associated with the Donald J. Trump for President Campaign were coordinating, wittingly or unwittingly, with the Russian government's efforts to interfere in the 2016 U.S. presidential election."[40][41][42]
Facts. They suck if you don't like 'em.
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