Aspiring jihadists looking to join the Islamic State army are often lured to the front lines with promises of changing the course of history and reclaiming a lost Islamic empire.

But at least for the less-skilled foreign recruits, the experience of fighting for the new caliphate is often brief and bloody. Kurdish and Iraqi commanders on the front lines of the war whom I interviewed in the last two weeks say that the suicide bombers and first-wave attackers deployed in Islamic State offensives are almost entirely made up of units of foreign fighters.

These highly risky missions mean that the new "immigrants" fighting the infidels end up as cannon fodder, while the more prestigious organizational jobs and less-risky defensive assignments go to Syrian and Iraqi Arabs.