Well these guys seem to be grabbing the headlines of late. They strike terror where ever they go. This seems to be their agenda. What surprises me is that, once these guys attack a place or are killing hostages, people exclaim in disbelief at their cruelty and ruthlessness. This is what they do. Terrorists kill and sabotage. That is what they are paid and trained to do. It just does not strike people that they should not be expecting mercy from these people. It is so absurd. The only way to get back at them is to be ruthless in our own way. We got to do what they do. That is the biggest turn off for any terrorist. Having to terrorize people who are not interested in their ability to strike terror.
It is the aftermath where hordes of civilians gather to pay homage and mourn the dead where these terrorists gain solace. This sort of mass behavior is a motivation for terrorists to do something for disastrous. Which for them would be extravagance undefined.