Do you remember when the hippies, members of the UN, and other enlightened anti-war and anti-US
Why is Russia in Syria? It isn't to embarrass the US. Embarrassing Obama, or any Democrat for that matter, in the area of foreign policy is not what one would call a "challenge."
Other geo-political reasons aside, the reason is oil. The reason is Russia's survival.
Russia, dependent on oil more than anything else, needs a higher oil price - ASAP.
Turmoil in the Middle East translates into higher oil prices.
Apparently, one Russia airstrike = 4% increase in oil.
Russia will need to turn it up a bit to get the 100% increase they need to break even.
UPDATED and BUMPED 10.19.15 3:30pm:
Dalan McEndree gives us an update at ZH, with predictions for Saudi Arabia and Russia: Oil Market Showdown: Can Russia Outlast the Saudis?