"Slay the unbelievers wherever you find them . . ." (Sura 9:5). The Islamic idea of jihad, which is derived from the Arabic root meaning "to strive" or "to make an effort," connotes a wide range of meanings, from an inward spiritual struggle to attain perfect faith to an outward material struggle to promote justice and the Islamic social system. The former meaning was emphasized by Sufis (Muslim mystics), who popularized a tradition describing the inner jihad as greater than the outer jih...