The New York Times reports the Islamic State calls them “inghimasi” — zealous foot soldiers who intend to fight to their deaths. And as the American-backed coalition has reclaimed territory from the group in Iraq and Syria, that fervor has kept prisoners from being much of a problem: The shooting only stops when almost every Islamic State fighter has been killed. But that could change as the coalition moves toward the Islamic State’s largest urban strongholds — Mosul, Iraq, and Raqqa, Syria — raising a potential problem for the United States. If the coalition is successful and thousands of ordinary members of a collapsing Islamic State have nowhere left to retreat, will they start to surrender in greater numbers? And if so, who will be responsible for imprisoning them?