They were supposed to rule as a tandem, the two-headed eagle of Russian politics. Vladimir Putin, the strongman, balanced in his actions by the relatively liberal-minded Dmitry Medvedev.
It was a farce from the start, of course, a way for Mr. Putin to retain power beyond 2008, when he was constitutionally barred from running for a third term as President. But the presence of Mr. Medvedev in the Kremlin between 2008 and 2012, and in the prime minister's post since then, nonetheless gave hope to Russian democrats and Western diplomats who were looking for a signal that the country wasn't headed all the way back to the bad old days of authoritarian rule.
Those hopes are dashed now, the façade smashed. Even before Mr. Putin sent Russian troops into Crimea – and threatened other parts of Ukraine – it was clear that Mr. Medvedev and his ideas no longer mattered in Moscow. Russian political analysts say the only question that remains now is whether he'll resign his increasingly powerless post as prime minister on his own, or hang around until Mr. Putin fires him.
"It's understood that Medvedev's days are numbered," said Nikolai Petrov, a professor of politics at Moscow's Higher School of Economics.
Mr. Medvedev, a soft-spoken, 48-year-old lawyer, is irrelevant in a Kremlin controlled by Mr. Putin and his allies from the security services. His beliefs in liberal economics and co-existing with the West are lonely banners blown about in the chilly nationalist wind that's currently blowing through Moscow.
The prime minister's slide into insignificance reflects the rapid waning of a progressive faction within the Kremlin that once competed for Mr. Putin's attention but has now been soundly routed by a coalition of social conservatives (think of the anti-"gay propaganda" law) as well as economic and foreign policy nationalists who pine for the days of the Soviet Union.
In fact, Mr. Medvedev's four years in the Kremlin are now being cast as a period where Russia lost its way, a time of inertia and compromise. "Medvedev presided over the worst decline of Russia since [the fall of the Soviet Union in] 1991," said Sergey Karaganov, a prominent nationalist intellectual.
Mr. Karaganov recently oversaw a panel of 200 experts who produced a paper on Russia's future that said the country was in "a state of economic and, most importantly moral and intellectual stagnation" that could be blamed largely on "mistakes made in 2008-2012."
It's a long way down from the heady days of six years ago when Mr. Putin surprised many by stepping aside and choosing Mr. Medvedev to succeed him instead of Mr. Putin's fellow ex-KGB operative Sergei Ivanov, who was rumoured to be the other name on the presidential shortlist.
Mr. Medvedev inspired hopeful headlines by using his first months in office to launch an economic modernization drive as well as an anti-corruption effort, putting two of the country's biggest problems – an aging industrial base and a culture of bribe-taking – square in the government's sights. He also engaged with U.S. President Barack Obama on the ballyhooed but ill-fated "reset" in relations between Moscow and Washington.
But just three months into Mr. Medvedev's tenure – during Russia's brief war with neighbouring Georgia – it was made clear that Mr. Putin was still the one calling the shots. Though foreign policy theoretically rested in the hands of Mr. Medvedev, it was Mr. Putin who declared that war had begun over the breakaway region of South Ossetia. It was Mr. Putin whom foreign leaders called to ask that Russia halt its offensive.
(Kremlinologists also noted that Mr. Medvedev, even while President, addressed Mr. Putin with the more respectful "vy," while Mr. Putin addressed Mr. Medvedev as "ty" – as though he were speaking to someone junior to him, which was correct age-wise, but not reflective of their constitutional powers.)
The turning point in the relationship between the two men appears to have been Mr. Medvedev's tacit acceptance of NATO airstrikes against Moammar Gadhafi's regime in Libya. Ignoring Mr. Putin's advice, Mr. Medvedev's ordered Russian diplomats to abstain, rather than use Russia's veto, in the vote at the United Nations Security Council that authorized the attacks. In the aftermath, the two men clashed publicly – a rarity in the tightly controlled world of Russian politics – with Mr. Putin calling the NATO intervention in Libya "a crusade" and Mr. Medvedev warning that such "unacceptable" talk could lead to a "clash of civilizations."
Six months later, a stone-faced Mr. Medvedev announced that he was stepping aside so that Mr. Putin could again run for the Presidency in 2012. Mr. Putin immediately accepted Mr. Medvedev's magnanimous gesture and declared Mr. Medvedev would be his prime minister (skipping over the fact that there were still parliamentary and presidential elections to win). But the tandem was finished.
"Medvedev was just the third term of Putin. Now we are in the fourth term and 2018 (when the next presidential election is scheduled) will be the fifth term," said Dmitry Gudkov, an independent deputy in Russia's parliament, the Duma. "We joke that Medvedev just kept Putin's chair warm."
Since returning to the Kremlin, Mr. Putin has further marginalized Mr. Medvedev by regularly chairing cabinet meetings, leaving his prime minister sitting off to the side, physically and politically marginalized. And while Mr. Medvedev made a symbolic visit to Crimea last week – the highest-level trip by a Russian official so far – he appears to have had little or no input as Mr. Putin has masterminded Russia's aggressive response to the revolution in Ukraine.
Moscow is left gossiping about who will replace Mr. Medvedev after his presumed departure from government. Mr. Ivanov, now Mr. Putin's chief of staff, is again considered a contender, as are nationalist firebrand Dmitry Rogozin, Russian Railways boss Vladimir Yakunin, Federation Council chairwoman Valentina Matviyenko, and Igor Sechin, a long-time Kremlin insider who now heads the state-owned oil giant Rosneft.
Popular Defense Minister Sergei Shoigu is another possibility, with many speculating he is now being groomed as Mr. Putin's eventual successor.
Of the names being bandied about, only Mr. Sechin and Mr. Shoigu are not on the list of those targeted for Western sanctions. No one is expecting Mr. Putin to give the West any kind of signal that he's backing down in the showdown over Ukraine.
In fact, many are expecting Mr. Medvedev to be retained a little longer in his post, so that he can be the fall guy later, when Western sanctions start to pinch Russia's already stagnating economy.
Few in Russia will mourn the end of the Medvedev era. He may be remembered best for having had the constitutional power to fire Mr. Putin – or at least to run against him in the 2012 election – but choosing not to use it.
"I was told that he still believes that he can come back in the next presidential election. Nobody in the country believes this," said Mr. Petrov, the politics professor.
"He chose one vote [Mr. Putin's] over 150 million voters."
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Mark MacKinnon