[KevinEldon]

ISIS doesn't have an Air Force; they can't really defend the desert they don't occupy event if it's terrorist with little strategic importance.

Had the maps shown ISIS with more territory someone might suggest a psychoigical effort was being made to scare people into supporting a more direct conflict with ISIS.

I do think it would be interesting to know how journalists draw these maps though.

[serpentor]

I dunno. Technicalities of vertical envelopment aside, once something is surrounded it's usually considered ceded to those who have it surrounded.

An inability to defend, contrasted with an unlikely target to be attacked, leaves you with ease of access as a defining quality of possession.