Adding to your list of enemies is never a sound strategy, yet ISIS' ferocious campaign against the Shia, Kurds, Yazidis, Christians, and Muslims who don't precisely share its views has united every ethnic and religious group in Syria and Iraq against them.

The Nazis and the Khmer Rouge went to great lengths to hide their crimes against humanity. Instead, ISIS posts its many crimes on social media for global distribution with seemingly no thoughts for the consequences.

ISIS is even at war with its most natural ally, al Qaeda in Syria.

Peter Bergen Quotes