The conspiracy nut part of me could also believe that they have a parallel stream of stupid and mentality ill ones that can be used to actually implement 'terrorist' attacks, but are supposed to be both directed, then contained and killed before they can inflict too much damage (or talk afterwards in front of a jury).

http://en.wikipedia.org/wiki/2014_Sydney_hostage_crisis

http://en.wikipedia.org/wiki/Charlie_Hebdo_shooting#Ch.C3.A9...