there are some very dicey lines to deal with this in this issue - humanitarian needs, aggravating russia, abandoning people in great need, allowing assad to keep doing his thing, etc.
i think asking the russians to remove their boy assad and let some moderate syrians take over is a reasonable option (although that hasn't been any kind of ringing success where we've done it in recent years).
i dunno. maybe blarg's nuclear option is the best bet. allowing it to continue as it's currently going doesn't seem like a good option, either.