The Italian government last month quietly began allowing armed American drones to fly out of an air base in Italy for military operations against Islamic State in Libya and across North Africa—a breakthrough for Washington after more than a year of negotiations, U.S. officials said. But Rome’s green light came with a caveat that underscores the challenges the U.S. faces as it attempts to win commitments from allies in the fight against the extremist group: The Italians granted permission for the drones to be used only defensively, to protect U.S. special-operations forces in Libya, the officials said. U.S. officials are still attempting to persuade the Italian government to allow the drones, based at Naval Air Station Sigonella on the island of Sicily since 2011, to be used for offensive operations like one the U.S. conducted Friday against a training camp near the border town of Sabratha, Libya, targeting a […]