I think that there is a historical component, from the origins of Islam to present day, that needs to always be placed within the context of present day difficulties.  This differs from the excesses of communism and nazism as it goes   back to cultural, tribal, racial, and religious, perspectives that developed in and around the Mediterranean and that divided people.  The Roman empire united peoples by sheer force until peoples subjugated rose as one to bring about its decline. These forces also declined as a result of disunity.  Faith then rose and united warrior cultures.  This included Islam that emerged, concurred, and  spread rapidly over the next 1500 years.  False prophets emerged throughout these ages with a message of submit to the one true faith or perish. Saladin, Suleiman  the Magnificent, The Mahdi, bin laden, al baghadi.  As with many conquering religions, the promise of a rightful place and better afterlife has been the koolaid backed by force and better weaponry.