The Mideast changed dramatically on April 30 of this year, when Sayyed Hasan Nasrallah, the leader of the Lebanon-based Shia terror group Hezbollah, gave a televised speech saying that Hezbollah would militarily enter the fight in Syria, on the side of the regime of Syria's president Bashar al-Assad, and then followed up by winning an overwhelming victory against Syria's opposition in Qusair. (See "6-Jun-13 World View -- Syria and Hezbollah gloat over victory in town of Qusair".)
That was the point in time when Syria's civil war turned into a war between Sunnis and Shias in the Mideast. That was the time when the Sunni terror group Jaish al-Muhajireen wa Ansar (the Army of the Immigrants) was formed in Russia's Chechnya province for the purpose of fighting against the Alawite/Shia forces of the al-Assad. That was the time when the trickle of Sunni jihadists coming to Syria to fight began to turn into a flood, arriving from central Asia, northern Africa, and Russia's southern Caucasus provinces.