You had two choices. You saw (you being the Obama admin) what happened in Iraq and Afghan. You saw what was happening in Egypt...you could try and make demands of the current Baathist government without destabilizing them. Or you could find a secular general...there were some and support them. Now its a mess and there are no good choices so your going to have to tell the Syrians that you are going to have carte blanche air superiority in Syria to attack Isis. There is already a war and its spreading...make the best bad choice and go all in.
I'm pretty sure a lot of republicans were upset about sticking his nose into egypt. The thought of us sticking our nose into other countries business, when we're on the verge of war with that country? Over what? because they kill americans that move there and sniff around? Um, if a bunch of Syrian "journalists" moved to washington DC and started "sniffing around" for "news stories", I"m pretty sure we'd call them spies lol. And if they were killed by criminals in the USA, so syria ordered airstrikes on it?
IMO, this entire premise - we need to go to war because journalists go into a zone with known terrorist rebels, sniffing around, and they get killed - makes ZERO sense. Seriously, some "repub" getbiggers said the first killing was "AN ACT OF WAR".