Well, it's easy to see that there are groups of people out there that have no respect for life, disregarding civil humanity and that they will even sacrifice themselves (suicide-bombers) for their cause.
People also know what agitates these groups of people, and it's entirely up to you, me and the rest of the people to take that information and process it and use it as we see fit. (Care for it or not)
For example, i know there is a group of people that would not mind dying for the cause, and their cause may be x, y or z.
If i know x, y or z agitates them, it is entirely up to me if i want to do x, y or z, since i already know the risks.
Risk Vs Reward.