What I find fascinating with all these cults, be it IS or nazism or the Khmer Rouge and a host of others, is that they have such power over the mind.
You have a line of what, 20 to 25 men there on their knees. So I guess they are about to be executed on a stage. But there are no guards in close attendance. There is also a crowd of what appear to be 'civilians' and if we are to believe what we are told these will have been forced to attend and forced to watch.
I would like think that if I was to be in either situation then I would resist. But the reality appears to be, people, the majority of people, simply don't. The threat of having your throat cut appears to make a person utterly compliant right up to the point of the throat cut.
It is odd.
As for various flags and their meanings, I am aware what an IS flag sort of looks like. But truly, if that other similar (but apparently fundamentally different) flag had been flying above those people about to be slaughtered i wouldn't have had sufficient knowledge of arabic script and nuance to know the difference. I certainly wouldn't run towards either flag if seeking refuge. Perhaps I'm just not paying enough attention.