A short detailed look at the role of the fraction-ridden Kurds, in both Iraq
and Syria; in particular what happened @ Mt. Sinjar and Kobane:http://defenceindepth.co/2015/03/25/...islamic-state/

The author Rob Thornton, who has spent time teaching in Iraqi Kurdistan, ends with a warning:
Without a common ‘Kurdish’ purpose they are just as likely to fight each other as they are to fight ISIL.