John Brennan is seen as the instigator of the bogus Russian collusion narrative against Trump

The Nation:

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... the “Republican memo,” as it has become known while we await its Democratic counterpart, indicates that some kind of operation against presidential candidate and then President Trump, an “investigation,” has been under way among top officials of US intelligence agencies for a long time. The memo focuses on questionable methods used by Obama’s FBI and Justice Department to obtain a warrant permitting them to surveil Carter Page, a peripheral and short-tenured Trump foreign-policy adviser, and the role played in this by the anti-Trump “dossier” complied by Christopher Steele, a former British intelligence officer whose career specialization was Russia. But the memo’s implications are even larger.

Steele’s dossier, which alleged that Trump had been compromised by the Kremlin in various ways for several years even preceding his presidential candidacy, was the foundational document of the Russiagate narrative, at least from the time its installments began to be leaked to the American media in the summer of 2016, to the US “Intelligence Community Assessment” of January 2017 (when BuzzFeed also published the dossier), the same month that FBI Director James Comey “briefed” President-elect Trump on the dossier—apparently in an effort to intimidate him—and on to today’s Mueller investigation.

Even though both have been substantially challenged for their lack of verifiable evidence, the dossier and subsequent ICA report remain the underlying sources for proponents of the Russiagate narrative of “Trump-Putin collision.” The memo and dossier are now being subjected to close (if partisan) scrutiny, much of it focused on the Clinton campaign’s having financed Steele’s work through his employer, Fusion GPS. But two crucial and ramifying question are not, Cohen argues, being explored: Exactly when, and by whom, was this Intel operation against Trump started? And exactly where did Steele get the “information” that he was filing in periodic installments and that grew into the dossier? In order to defend itself against the memo’s charge that it used Steele’s unverified dossier to open its investigation into Trump’s associates, the FBI claims it was prompted instead by a May 2016 report of remarks made earlier by another lowly Trump adviser, George Papadopoulos, to an Australian ambassador in a London bar. Even leaving aside the ludicrous nature of this episode, the public record shows it is not true. In testimony to the House Intelligence Committee in May 2017, John Brennan, formerly Obama’s head of the CIA, strongly suggested that he and his agency were the first, as The Washington Post put it at the time, “in triggering an FBI probe.” Certainly both the Post and The New York Times interpreted his remarks in this way. Equally certain, Brennan played a central role in promoting the Russiagate narrative thereafter, briefing members of Congress privately and giving President Obama himself a top-secret envelope in early August 2016 that almost certainly contained Steele’s dossier. Early on, Brennan presumably would have shared his “suspicions” and initiatives with James Clapper, director of national intelligence. FBI Director Comey, distracted by his mangling of the Clinton private-server affair during the presidential campaign, may have joined them actively somewhat later. But when he did so publicly, in his March 2017 testimony to the House Intelligence Committee, it was as J. Edgar Hoover reincarnate—as the nation’s number-one expert on Russia and its profound threat to America (though, when asked, he said he had never heard of Gazprom, the giant Russian-state energy company often said to be a major pillar of President Putin’s power).

The question therefore becomes: When did Brennan begin his “investigation” of Trump? His House testimony leaves this somewhat unclear, but, according to a subsequent Guardian article, by late 2015 or early 2016 he was receiving, or soliciting, reports from foreign intelligence agencies regarding “suspicious ‘interactions’ between figures connected to Trump and known or suspected Russian agents.”

In short, if these reports and Brennan’s own testimony are to be believed, he, not the FBI, was the instigator and godfather of Russiagate. Certainly, his subsequent frequent and vociferous public retelling of the Russiagate allegations against Trump suggest that he played a (and probably the) instigating role. And, it seems, a role in the Steele dossier as well.
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§ Originally it was said that his Russian sources were highly paid by Steele. Arguably, this might have warranted the risk. But subsequently Steele’s employer and head of Fusion GPS, Glenn Simpson, wrote in The New York Times that “Steele’s sources in Russia…were not paid.” If the Putin Kremlin’s purpose was to put Trump in the White House, why then would these “Kremlin-connected” sources have contributed to Steele’s anti-Trump project without financial or political gain—only with considerable risk?

§ There is the also the telling matter of factual mistakes in the dossier that Kremlin “insiders” were unlikely to have made, but this is the subject for a separate analysis.

And indeed we now know that Steele had at least three other “sources” for the dossier, ones not previously mentioned by him or his employer. There was the information from foreign intelligence agencies provided by Brennan to Steele or to the FBI, which we also now know was collaborating with Steele. There was the contents of a “second Trump-Russia dossier” prepared by people personally close to Hillary Clinton and who shared their “findings” with Steele. And most intriguingly, there was the “research” provided by Nellie Ohr, wife of a top Department of Justice official, Bruce Ohr, who, according to the Republican memo, “was employed by Fusion GPS to assist in the cultivation of opposition research on Trump. Ohr later provided the FBI with all of his wife’s opposition research.” Most likely, it found its way into Steele’s dossier. (Mrs. Ohr was a trained Russian Studies scholar with a PhD from Stanford and a onetime assistant professor at Vassar, and thus, it must have seemed, an ideal collaborator for Steele.)
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§ Was Russiagate produced by the primary leaders of the US intelligence community, not just the FBI? If so, it is the most perilous political scandal in modern American history, and the most detrimental to American democracy. And if so, it does indeed, as zealous promoters of Russiagate assert, make Watergate pale in significance. (To understand more, we will need to learn more, including whether Trump associates other than Carter Page and Paul Manafort were officially surveilled by any of the agencies involved. And whether they were surveilled in order to monitor Trump himself, on the assumption they were or would be in close proximity to him, as the president once suggested in a tweet.)
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There is much more.

This looks like another area of inquiry for Congressional committees to explore.  Brennan appears to be an active leaker who was desperate to scuttle the Trump campaign and his presidency.  He is said to have desperately wanting to keep his job if Hillary Clinton were elected. 

It should be noted that The Nation is a liberal publication.  It certainly has no affinity for Trump or the Republicans.  If they are right about Brennan being a source for Steele's dirty dossier, it would be difficult for the mainstream media to continue ignoring the story of the Democrats involvement into what has devolved into a coup attempt.