Former Russian double agent Sergei Skripal and his daughter Yulia remain in critical condition, three days after they were found unconscious on a bench in the English city of Salisbury. The pair were presumably poisoned by what is so far referred to as an "unknown substance."

Britain's counter-terrorism police have now taken over the investigation, and already, the finger of suspicion is pointing towards Moscow, in large part because of similarities between this case and the 2006 poisoning of another former Russian spy, Alexander Litvinenko, in London. A public inquiry concluded that the Litvinenko murder was "probably" carried out with the approval of Vladimir Putin.

Another reason for suspecting Moscow's hand comes from 2010 video footage in which the Russian president himself warns Russian spies not to betray their country. "Traitors will kick the bucket, trust me," Putin remarks. "Whatever they got in exchange for it, those 30 pieces of silver they were given, they will choke on them." The video was made the same year Skripal, who had been sentenced to 13 years of imprisonment in Russia, was released as part of a spy swap.

But there's more, as Moscow correspondent Emmanuel Grynszpan writes in the Swiss daily Le Temps: "On Monday, March 5, before news of the incident was made public, Vladimir Putin congratulated the Russian secret services for neutralizing more than 400 foreign spies last year. Speaking in front of his former colleagues from the FSB, of which he once was director, he asked them to keep up their efforts to block ‘any attempts of foreign intelligence services to obtain political, economic, technical and military information.'"

Alexander Litvinkenko hospitalized in London in Nov. 2006 — Source: Steve Baker

"The spy mania is unfolding against a backdrop of nuclear rivalry revived by the Russian president's annual state of the nation speech last week," Grynszpan adds. "On March 1, Vladimir Putin said that Russia had developed four new types of ‘invincible' nuclear weapons without their equal anywhere in the world, capable of piercing through any defense system, giving his country strategic superiority."

The timing for both the suspected Russian poisoning of Skripal and the nuclear weapon boast indeed raises many questions, not least because of the upcoming presidential election, set to take place March 18.

"Did Vladimir Putin wave paper missiles to fan the electorate's patriotic flame two weeks from the election?" Grynszpan asks. "Or is it just scare tactics to force Washington to renegotiate some cases that are annoying Moscow? In power for 18 years, Vladimir Putin continues to capitalize on an alleged Russian humiliation that resulted from the break-up of the USSR, which he's described in the past as ‘the greatest geopolitical catastrophe of the 20th century.' By proclaiming that ‘Russia containment has failed,' he's challenging the outcome of the Cold War and trying to appear in the eyes of the Russian population as the instrument of their revenge against the United States."

It's meant to be a reminder to other Russian operatives of the potential risks of working with foreign intelligence agencies.

The logic regarding the timing of Putin's nuclear weapon boast seems implacable. But what if the real motive behind the poisoning of Sergei Skripal — if Moscow is indeed behind it — was to be found elsewhere? This is the theory defended in The Guardian by reporter Shaun Walker.

"Suggestions that this could be some kind of vote-winning ploy, coming two weeks before presidential elections Vladimir Putin is certain to win, seem unconvincing," Walker writes. "Many Russians are patriotic and have bought into the Kremlin's aggressive new foreign policy, but it is unlikely that the assassination of a former spy of whom few had heard would do much to whip up popular passions."

More likely it's meant to be a deterrent, a reminder to other Russian operatives of the potential risks of working with foreign intelligence agencies, the reporter argues.

"Every year, Russia's top security officials speak of active attempts by the CIA and other western agencies to recruit Russians. Part of this is propaganda for domestic consumption, but there is no doubt that western spy agencies are active in Russia," The Guardian piece reads.

Suspicions abound. And yet, like with the Litvinenko case, we might never find out for certain who poisoned Skripal and his daughter — or why. Still, one thing that is clear from the events of the past few days is that the relentless power struggle between Russia and the West isn't just taking place in Syria.

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