Why did we decide to over through Assad in the first place? Didn’t we learn any lessons from from Iraq or Libya. These animals only understand one thing, brute force.
There was no logical, tactical reason. Just as there was no reason to overthrow Gaddafi.
Unless the migrant crisis, the destabilization of Europe, and ultimately, war were the goals.
Don't forget, we had to make up a fictitious terrorist organization out of whole cloth, ("The Khorosan Group") and said they posed an "imminent danger to aviation", as the casus belli to start bombing Syria and insert ourselves into this mess. That would suggest they're doing this for reasons they're not exactly comfortable with sharing publicly.