Tartus, Syria, where the Russians have a Naval Base...Syria isn't exactly the most stable of places these days, so it multiplies the importance of her Black Sea Fleet.
But... That’s the point. There was little danger of Russia losing their bases in Crimea. Ukraine wasn’t going to break that lease unless threatened - even the EU and the Nationalists know they need the money.
Besides, after Maydan, what was most likely to happen (B4 Russia took Crimea)? Tymoshenko ends up as Pres., she’s always been able to work with Putin, what’s the problem? Now she’s pissed, and more extreme elements have a better shot in May’s elections.
Speaking of money, Putin / Russia are going to have to spend LOTS more rubles now, to prop up Crimea, even if things go very well for them from here on out, and no significant military action occurs. And in the long run, while I don’t expect Europe to be energy independent for a long time, they do now see the need for alternatives to Russian supply. Plus, Euro countries surely trust US “protection” even less than B4. A 0.3% increase in defense spending as a % of GDP by Europe would require, oh, at least 1% by Russia to match it, because Europe’s economy is so much larger. Russia would have been much better off simply spending their money on the fleet and other capabilities, without alarming the West.
Something more is at play.