I think this indicates that Iran has become the de facto regional power in the Middle East. From staging aircraft at Iranian airbases, Hezbollah and IRGC fighters on the ground in Syria to arming Iranian Shiite militias in Iraq. I think that is why the Gulf states are so hell bent on removing Assad by supporting ISIS and other Sunni fighters. We've always been cognizant of the Shia/Sunni divide so this is nothing new. What is new, I think, is that we are seeing a shifting acknowledgement, a calculation in effect, by Russia and the US of Iran's status as a 'stabilizing influence'. The question now is how will the Sunnis and the Gulf states respond? Personally, I think this might lead to a major regional sectarian conflict which goes beyond ISIS.