I'm not sure that the civil war in Syria comes from US intervention, or even from ISIS. ISIS tried to take advantage of an existing situation, which was triggered by Assad's brutality to (initially non-violent) protests of his regime.
http://www.independent.co.uk/news/world/middle-east/syria-cr...
And the US had been covertly funding the opposition for at least 5 years before the war erupted:
http://www.csmonitor.com/World/terrorism-security/2011/0418/...
Like, coordinating coups and dropping bombs over and over again tends to have that effect.