>extremist Muslims or familiarity with what the Quran and hadiths

You can easily find stuff in the Bible and the Torah or Talmud that would shock you. And Israel even acts on the latter. But conveniently it's just the Muslim world, one beset with colonial extraction for centuries, that you care about. Not the people in the US who supported wars killings hundreds of thousands over the last few decades for religious reasons. Hmm.

> the Muslim world, one beset with colonial extraction for centuries

Surely you mean on the side of extractors? The Ottoman Empire practiced mass movement of people (sürgün), basically settler colonialism; earlier Umayyad and Abbasid caliphates are among the largest empires in history, and their population was mass converted to Islam.