Over the last few years Russia has been trying to refurbish its naval base in the Syrian port of Tartus. Established in the early 1970s, it was never much more than a fenced off portion of the waterfront, where one pier, and some floating piers brought in by the Russia, along with a repair ship or two, took care of maintenance needs of Russian warships (and spy ships) in the Mediterranean during the last two decades of the Cold War. In the 1990s, the Russian facility in Tartus fell on hard times. For most of that decade, there were only a few caretakers, and few visits from Russian ships of any sort. Three years ago Russia announced that its Tartus facility would be refurbished to support Russian ships on anti-piracy duty off Somalia. The Tartus piers would be repaired and made longer. Currently the few working piers can only hand ships under 100 meters (310 feet) long. During the Cold War the Russian Navy had a lot of small ships like that, but now most major Russian warships are much longer.
I've never doubted that the base was pretty sad by base standards.
But it is the only overseas base Russia has. They may see far more value than we would in keeping it.
Still, Russia doesn't seem like they are willing to fight to keep it. They haven't landed any marines there yet. And they have said that they'd leave if rebels fired on them. Yet they'll be happy to keep it and improve it if Assad survives and holds the port. So far Russia hasn't turned on Assad even if Russia seems to be wondering if they should hedge their bets.
Tartus is their only overseas base--as insignificant as it seems. Psychologically, just existing might be the most important role Tartus provides Russia.
UPDATE: More on the base. It isn't much, but it is important to Russia.
But depending on Assad's fortunes, the Russians can't know if they will retain this base.
If I was in charge of Russia, I'd try for a big play to flip economically distressed and angry Greece. The Cold War began to resist Soviet attempts to subvert Greece. Maybe Russia can pick up the struggle and gain a base in the Mediterranean. Not with armed insurrection. Would Greek anger at German and EU bankers be enough to make a big Russian economic bribe seem like a good idea?
I mean, this need isn't anything new. Russia once did have a naval base on Greek soil a couple hundred years ago. Maybe Corfu rather than Crete would be Russia's dream base.
Would Russia want to pay the price? Or would it be simpler and cheaper to pay the price to whoever wins the Syrian civil war? Would the rebels be receptive if the price was high enough?
