People are always driven by something. Some times it is trying to get revenge for abuse as a child, some times it is wanting revenge against the government, other times it is religion. No one is saying that religion is his motivation because he is muslim, that has nothing to do with it. They are saying it was his motivation because he made it clear that it was.
Even cowards need motivation and something to believe it to motivate their cowardly selfs to make a sacrafice. Those radical things they cling to as excuses are dangerous, because that gives them the excuse and courage to do what they want to do. And really, do you think that if he did not believe in radical islam that he would have done that? Probably not, so it is important.
No, taking things (anything) out of context can. As long as that is not done, it is a relevant part of the discussion. What about deliberately ignoring an important part of situation? Can that be a perversion of the discussion?
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