I really don’t know anything about how intelligence briefs are written, but one thing I know for certain (a priori) is that they barely accommodate any wrangling over epistemology and metaphysics, albeit a few fine thinkers such as Alexandre Kojève (KGB), AJ Ayer (MI6), HLA Hart (MI5), Stuart Hampshire (unaffiliated cryptanalyst, but investigated by MI5 for being a Russian mole), were considered to be part of the intelligence community. Despite that, my hunch is that most intelligence briefs, with the the exception of the very best, can be wrought with what-if-scenarios as in the present Brookings piece.
The logic behind the writing is as simple as this: "If “we” (in the United States or the West) released these documents, the motive would apparently be to embarrass Putin.” But if Putin isn’t implicated with good reason while the West is in deep shit, then blame the entire #PanamaPaper leaks on him. Then what if we (in the West) fail to implicate him with good enough reason?
We know nothing as to the source of the leak. But the writer builds a scenario out of a figment of his imagination. The imagination of a schizophrenic in a Dostoevsky novel, so to speak. The writer surmises, "If the Russians are behind the Panama Papers, we know two things and both come back to Putin personally: First, it is an operation run by RFM, which means it’s run by Putin; second, it’s ultimately about blackmail. That means the real story lies in the information being concealed, not revealed. You reveal secrets in order to destroy; conceal in order to control. Putin is not a destroyer. He’s a controller."
So, in the end, it boils down to a blame game, borne out of the realization that Putin wasn’t sufficiently implicated in the scandal that already claimed high profile victims in Iceland and the UK, which the writer alludes to as partners that fell as collateral victims if it was an inside (Western) job.