re: the Arab Street
There is no "Arab Street"...if there is I kinda wonder what they do, we have been told that they have been "rising" since 1947.
Unfortunately for the Arabs the street is a cul de sac.
One of the realities the Muslim world and the Arab world in particular has to face is their general weakness and strenght of disorganization and lack of unity..
My own guess on the killers - Syrian military operating without Asaads orders.