When faced with a muddled trail, investigators sometimes go back to the beginning and take backbearings. That's was George Smiley's plan when he wanted to find out how the rot started in the Circus.
[Smiley’s] premise was, that in briefing [the mole], Karla was exposing the gaps in Moscow Centre’s knowledge; that in ordering [the mole] to suppress certain intelligence which came the Circus’s way, in ordering him to downgrade or distort it, to deride it, or even to deny it circulation altogether, Karla was indicating the secrets he did not want revealed.
‘So we can take the backbearings, can’t we darling?’ murmured Connie Sachs, whose speed of uptake put her as usual a good length ahead of the rest of the field.
‘That’s right, Con. That’s exactly what we can do,’ said Smiley gravely. ‘We can take the backbearings.’ …
By minutely charting [the mole’s] path of destruction–his pugmarks as he called them–by exhaustively recording his selection of files; by reassembling, after aching weeks of research if necessary, the intelligence culled in good faith by Circus outstations, and balancing it, in every detail, against the intelligence distributed by [the mole] to the Circus’s customers in the Whitehall marketplace, it would be possible to take backbearings–as Connie so rightly called them–and establish [the mole]’s, and therefore Karla’s, point of departure …"
George Smiley is fictional and British. Still it may be profitable in real-life Washington to go back a few years, as Dana Priest in the New Yorker does, to unravel a problem similar to that which baffled Sherlock: why did the dog not bark in the night? Or as Priest puts it,why couldn't the Obama era intelligence community detect Russian meddling.
After failing to detect and stop Al Qaeda’s 9/11 attack sixteen years ago, Congress more than doubled the budget of American intelligence agencies and gave them unprecedented secret authorities. ...
And yet, last year, these vastly larger agencies failed to defend, or even warn, the American public against the most audacious Russian covert operation toward the United States since the end of the Cold War. Only after the fact, when a Russian disinformation campaign had already tainted the 2016 Presidential election, did the Office of the Director of National Intelligence, another vast post-9/11 creation, disclose the Kremlin’s interference. The unclassified January, 2017, report, made public by the O.D.N.I., included only the thinnest of evidence, leaving many people wondering if it were true. Whether the Russian campaign actually changed the outcome of the election is impossible to know, but it clearly succeeded at exacerbating political divisions in the United States and undermining the credibility of the results.
Unlike 9/11, the Russian campaign did not occur without warning on a quiet fall day. Rather, it unfolded over at least six months on Americans’ social-media accounts—hardly the stuff of spy novels. Kremlin leaders had signalled their plans years in advance. The Russian playbook wasn’t a secret, either. It had been well documented by European governments, researchers, and journalists after the Kremlin’s information operations to destabilize Estonia, in 2007; Georgia, in 2008; Ukraine, in 2014; and Britain, in the leadup to the 2016 Brexit vote.