…Stop the rebels, including the same people who bombed the WTC. OR, throw out Assad, who kept Syria in a state of relative quiet (compared to now) for years with his brutal dictatorship.
Another alternative: stay the hell out of there, unless you feel the urge and will fund it yourself and take on the job personally.
Update: The Russians have arrived to prop-up the Assad regime. What is our beef with the Russians? Their oil industry competes with ours? Their vodka industry? Their adult singles industry? What? Let them have Syria. I can’t think of a worse present to someone we don’t like. Even though I don’t hold anything against Russia myself, for those who imagine there is some problem with friendly relations with Russia, how could you beat a booby prize like Syria? Besides that they will be fighting ISIS, just like the Iranians. Life is good.