If Assad is taken out, we’ll have to send in 200,000 troops (if not more) to achieve and maintain order.
Once assad is taken out obama will recall our units; how, I don't know, but he will find a way (maybe capitulating to Russia, being the peaceful guy he is and "de-escalating" things"). Iran goes full tilt after that against The Sauds. Russian oil goes through the roof on exports, here in the U.S. we suffer a crippling energy blow as we stabilize and are (finally) forced to use our own means of producing energy and are not messing with OPEC. (Venezuela would love for things to play out that way as well,they are in the hurt locker over oil prices)
Actually order will come on the heals of the Fall of Damascus...about 7 years later.