I saw a video on ISIS the other day. ISIS is trying to take control of the Levant. Israel, Palestine, Syria and Iraq to create a Islamic State ruled by Shria law. ISIS is a largely Sunni group that is killing Shia. Long standing enemies the U.S. and Iran are in talks. The U.S. wants Iran to become embroiled in a mostly Sunni/Shia conflict because Ethnically Iran in 90 percent Shia.
The central divide in the two Ethnicities may be the very match that lights a major conflict in the Middle East.
Most people do not know that the only large difference between the Sunni and Shia is literally how the successor of Muhammad should have been chosen 1400 years ago.