This is what I read in the article “Fueling Terror: How Extremists Are Made” on the Scientific American website:
In particular, we are learning that radicalization does not happen in a vacuum but is driven in part by rifts among groups that extremists seek to create, exploit and exacerbate. If you can provoke enough non-Muslims to treat all Muslims with fear and hostility, then those Muslims who previously shunned conflict may begin to feel marginalized and heed the call of the more radical voices among them. Likewise, if you can provoke enough Muslims to treat all Westerners with hostility, then the majority in the West might also start to endorse more confrontational leadership. Although we often think of Islamic extremists and Islamophobes as being diametrically opposed, the two are inextricably intertwined. And this realization means that solutions to the scourge of terror will lie as much with “us” as with “them.”
You may wonder why so many politicians (and citizens!) fail to understand this; I do wonder too. But we can see it all over the world, in the USA as well as in Belgium, or in Iraq, etc. etc. Too bad the obvious conclusion from this fact is so hard to apply – but it is not impossible, if we really want it.