The Piltdown man – perhaps the most famous fraud in the history of paleontology –combined a 600-year-old skull, an orangutan’s jaw and a chimpanzee’s tooth to feign being the remains of the Missing Link between man and the apes.

Now, more than a century later, the Piltdown man has come to US politics with Friday’s release of a declassified memo by Devin Nunes, the chairman of the misnamed House intelligence committee. The Nunes memo connects mismatched shards to suggest a missing link between Robert Mueller’s Russia investigation and the Hillary Clinton campaign’s efforts to discredit Donald Trump.



The triggering event was a 21 October 2016, foreign intelligence surveillance court (Fisa) warrant for electronic surveillance of Carter Page, an energy consultant and sometime Trump adviser who had been under FBI scrutiny since 2013. According to the Nunes memo, a dossier prepared by Christopher Steele and partly funded by the Clinton campaign was “an essential part” of the rationale for the warrant.

We can quibble about what “an essential part” means. Especially since the FBI in an unprecedented Wednesday press release stated: “We have grave concerns about material omissions of fact that fundamentally impact the memo’s accuracy.” Unmentioned by Nunes were all the other documents that the FBI and the justice department presented to the Fisa court to justify eavesdropping on Page.



'Nunes memo' published after Trump declassifies controversial document Read more

But even if you accept the world according to the House Republicans (a personal plea: don’t), Page represented a circuitous route to get at Trump. Page had withdrawn from the campaign a month earlier in the wake of news stories about his suspicious meetings in Moscow. And Trump himself later belittled Page as “a very low-level member of I think a committee for a short period of time.”



To summarize: in a document that the FBI called inaccurate, House Republicans claim that the Democrats had some shadowy role in a pre-election Fisa warrant against a “very low-level” Trump adviser who had already left the campaign. Compared with the Nunes memo, the never-ending, dry-hole Republican Benghazi investigations look like textbook examples of prudent congressional oversight.



To Trumpian true believers, the Nunes memo proves that the FBI and the rest of the Deep State were conspiring to throw the election to Hillary. Of course, this omits the pesky detail that on 28 October 2016, the FBI director, James Comey, announced that he was reopening the Clinton email investigation based on what had been found on Anthony Weiner’s computer.



Guess which late October event had more effect on wavering 2016 voters: Comey’s dramatic public statement raising fresh doubts about the Democratic nominee or a secret warrant against a peripheral Trump adviser?



Who is Devin Nunes and why is he sowing confusion in the Russia inquiry? Read more

The Nunes memo makes one major concession to reality – the FBI opened its Russian investigation three months before the Steele dossier was used, in some fashion, to justify the Page Fisa warrant.



In a scene that might have been lifted from the 2016 version of All the President’s Men, a young Trump foreign policy adviser named George Papadopoulos had the foolish notion of trying to drink an Australian diplomat under the table. Instead, Papadopoulos (who later pleaded guilty to lying to the FBI) blabbed that the Russian government had a trove of hacked Hillary Clinton emails. Once the Australian government passed this nugget on to Washington, the FBI opened up its Russian front.



Ever since Watergate, the standard for any scandal is whether there is a smoking gun left next to a corpse. In the case of the Nunes memo, we lack a body and the gun is a child’s toy pistol.



Trump's release of Nunes memo is Nixonian – but today's GOP won't resist Read more

All this raises the question of why Nunes, the Republican majority on the House intelligence committee, Paul Ryan and Trump were so willing to go to war with the FBI over a cap-gun memo. We even have hyper-ventilating Republican congressmen shouting “treason”.



The glib answer is that this a pretext for Trump to fire Mueller and the deputy attorney general, Rod Rosenstein. But Mueller is never mentioned in the Nunes memo and Rosenstein makes only a cameo appearance. More attention is devoted to articles by journalists David Corn (Mother Jones) and Mike Isikoff (Yahoo News).



Perhaps a more convincing answer is that we have reached that alarming moment when right-wing Republicans actually believe the conspiracy theories peddled by the likes of Sean Hannity on Fox News, who claims the memo reveals an “attempted coup” against Donald Trump plotted by the “Deep State”. At least, the original fabricator of the Piltdown man knew that it was all a hoax.



Walter Shapiro, who has covered the last 10 presidential campaigns, is a columnist for Roll Call and a lecturer in political science at Yale.



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