What are we to make of this?
This is 50s-style brinkmanship “diplomacy”, characteristic of the Soviet era; they’re aware that there’s a massive realignment going on, again, and have been pushed out of the Middle East over the past 38 years (starting with the 1973 war, and the roots go back at least to the 1967 war). They’ve been reasserting themselves here in our hemisphere (kept Cuba, gained Venezuela, regained Nicaragua, and have been struggling against the rise of Brazil), and the Arab Spring and whatnot will have been seen by them to be a response to their intrigues.
Turkey (whether we like it, or them, or not) is a NATO member, and it has been on a diplomatic offensive for some years now, under Erdogan. Whether or not Turkey turned on Assad’s regime, these moves by Russia are to try to diplomatically isolate Turkey, and that means a Russian shift toward support of Assad. Had the Turks stuck with Assad, Russia would have been much more direct in its support in an effort to wean Turkey and Syria apart.
Russia already supports Iran — and that’s difficult for them because Iran grows more isolated, and it’s only a matter of time before that regime goes. Iran is the Achilles’ Heel of Russian foreign policy in the Middle East, a real lose-lose situation. So, they’re all in.