Russia has almost no strategic interests in Syria. The vaunted "naval base" on the Mediterranean coast at Tartus is no more than a pier and a floating repair shop. Its loss would have no significant effect on Russian naval capability.
As a customer for Russian arms, Syria represents only 5 per cent of total sales, and the major proposed deals - for air-defence missiles and advanced fighters - have been postponed or abandoned in the interests of good relations with the West and Israel.
The basis for Russian support of President Bashar Al Assad, even as his regime looks ever shakier, is not shared interests. It is simply nostalgia among the Moscow elites for Russia's great-power status, which has led them to try to prevent "the final disappearance of the last ghostly traces of Soviet might".
These views come not from some disgruntled Russian opposition figure, but from a leading Russian defence consultancy, the Centre for Analysis of Strategies and Technologies, which provides confidential advice to Russian military chiefs. This analysis goes some way to explaining one of the conundrums of the Arab revolts: why is Russia seemingly determined to get on the wrong side of history in the Syrian crisis?
It is certainly not out of admiration for the Syrian president, according to the think tank's information officer, Ruslan Aliyev. "No one in Russia really thinks Assad is a good or helpful guy," he told the BBC.
So the root of the issue is emotional, rather than one of fundamental interests. If that is the case, then does it make the stalemate over Syria easier to resolve, or harder?
There is not much time left to ponder such issues. In a last effort to rescue his peace mission, Kofi Annan, the envoy of the United Nations and the Arab League, has called a meeting tomorrow in Geneva of his new Action Group for Syria. He hopes the meeting will endorse a political transition plan which would lead to a national unity government, including members of the opposition.
Russia has accepted the invitation but Iran, Syria's closest ally that Moscow had insisted should be at the table, is not invited. Nor is Saudi Arabia, the most vocal backer of the armed Syrian opposition - apparently to balance the absence of Iran, as if the two absences would cancel each other out.
It is understood that Russia has accepted the principle of a political transition plan, but only in the diplomatic sense, with the key details fudged.
The western powers insist that political transition means the exit of Mr Al Assad, perhaps to retirement in some quiet backwater of the former Soviet Union. The Russian foreign minister, Sergei Lavrov, has been quick to quash this idea. The aim of the meeting, he says, is to discuss a ceasefire and start a dialogue, "not to predetermine the shape of a possible government of national unity".
Clearly, there are voices in Moscow arguing that Russia should be part of the solution to the Syrian crisis, not fight a rearguard action in favour of the last of the dynastic republics. But it seems that the motivation in President Vladimir Putin's mind is not about where Russia's long-term interests lie, but rather in an emotional reaction to being outsmarted by the western powers in Libya, where they ignored Russian objections and went to war to overthrow Muammar Qaddafi.
Konstantin Eggert, a Russian diplomatic commentator on Kommersant radio, argues that Russia has few interests in the Middle East and therefore has been free to wage what he calls a "limp mini-war" with the US in the region.
What drives the Kremlin's desire to preserve the crumbling status quo, he says, is the spectre of mass protest such as the Orange Revolution that gripped Ukraine in 2004. Ultimately domestic concerns, and the prolongation of the Putin era, take precedence over foreign policy. At some stage, Russia is going to have to put together a new Middle East foreign policy "on the run".
Is this the time that Russia is going to reformulate its Syria policy? If there is slackening of support for the Assad regime, it is painfully slow to appear, and we have still to hear it from the lips of Mr Putin.
If Russia was the major obstacle to resolving the crisis a year ago, the time has passed when a change of heart in the Kremlin could restore calm. Mr Al Assad now acknowledges that his country is in a civil war. Last week was the bloodiest since the uprising began, according to unofficial figures. The opposition is increasingly well armed.
Now that there are so many in the opposition under arms, and after so much killing by the army and its Alawite militias has poisoned relations between Syria's religious communities, it is hard to see how the insurgents will be satisfied with anything less than victory.
Mr Annan is still at the stage of coalition building: he wants Russia inside the tent. But no one should be under any illusion that this is the key to ending the civil war in Syria. Back in February, it might have made a difference. Today, it seems more like a diplomatic sideshow to the rumble of gunfire.
On Twitter: @aphilps