It all comes from the regime change policies of BOTH GWB and Obama. It's led to vacuums everywhere. Add that to arming and training people to fight the wars and we've armed, financed, and trained ISIS and created the vacuum where they flourish.
And Obama is STILL working for regime change...in Syria and to weaken Putin. And he's still arming and training "friendly rebels" to fight for us. Why isn't someone stopping this madness?