&gt;<i>Also they did not come from poor social classes. They don&#x27;t have the &quot;excuse&quot; of having grown in a troubled society, they were not desperate because of their shitty life</i><p>They were &quot;westerners&quot; only in their nationality not in their ethnicity. For some western societies it&#x27;s difficult to imagine the difference, but it exists -- not everybody gets assimilated to the culture he lives in, especially if there&#x27;s another culture he feels he belongs to by inheritance.<p>For those of people (who are not the majority of ISIS, but a small minority) it&#x27;s about a twisted idea of revenge for what happened and happens to their (origin) countries and to people of the same faith there, and how the west views and treats them -- not about struggling with poverty.