The Syrian civil war might still have happened if the US hadn't already destabilized Iraq. But Iraq directly led to ISIS, which is partly composed of Iraqi ex-B

The Syrian civil war might still have happened if the US hadn't already destabilized Iraq. But Iraq directly led to ISIS, which is partly composed of Iraqi ex-Baathists and holds a large amount of ground in Iraq along traditional Sunni divisions; arguably ISIS would not be the organization it is today if its scope had been geographically and politically limited to Syria.