Will air assault against IS in Syria be used to effect regime change?

[Xithras]

17. There's a real question about what happens if Assad asks Russia for help.

While Syria does have the capability to bring down U.S. fighters and drones (they have the same Buk missile system that was recently used in Ukraine), doing so would lead to the immediate annihilation of the Syrian government by U.S. aircraft. Our government seems to be counting on this knowledge, expecting that Assad will just stand back and let us do our thing.

The wildcard in the situation is the Russians. Syria is has been a Russian ally since the 1970's, and is a huge military client of Moscow's arms traders. Syria is also home to Russia's only naval base in the Mediterranean. If Assad called on the Russians to help him repel American violations of Syria's airspace, there's a real question as to how the Russian's would answer. A newly assertive Russia might embrace the opportunity to flex its muscles and display its willingness to defend an ally (or to avoid the impression that they leave their allies hanging when push comes to shove). On the other hand, the Russian people tend to take a hardline position against Islamic extremists (given their own experiences in Chechnya and Dagestan), and there is the potential for serious political blowback if the Russian people interpret his actions as helping I.S. terrorists.

It's a real coin flip at this point, IMHO.