the Syrian government has been propped up and heavily influenced by Russia since before the civil war
Russia has a strategically important military base in Syria
Syrian government is in chaos
Russia has been supplying the Syrian government with weapons and assistance the whole time this civil war has been going on
Russia sees that all the work they've been doing is still not enough
Russia is forced to commit troops and military to the region....
This is not chumping obama... this shows Russia's desperation...
They have to believe the government is going to be toppled and in turn Russia will lose it's military base in the region unless they do something drastic....
They already lost the puppet government in Ukraine (which we helped replace with a pro-west leader) and violated numerous international laws trying to keep the base in Crimea....
Russia = desperate
I think firstly you have to acknowledge that the Syrian conflict is not just the Syrian government vs. The FSA.
There are so-called moderate elements (which the US is directly supporting) and of course ISIL as well.
The US government is active in Syria on two fronts; one is to overthrow the Assad regime and the other to push back and destroy ISIL.
They have not been successful on either front. ISIL has gained more territory than ever before, the US military has their weapons in the hands of extremists, and many of the so-called moderate elements have defected to both ISIL and the Al-Nusra front.
Russia on the other hand is bombing both rebel factions and ISIL and propping up the Syrian govt as you said. More importantly though, they are winning the PR war. They are showing that the Obama government is not only acting timid when it comes to ISIL, but is in fact indirectly supporting these jihadist groups.
None of the actors in the play are particularly good, but Russia is managing to show the hypocrisy of the U.S when it comes to the conflict.