After seizing five oil fields and Iraq's biggest dam, Sunni militants bent on creating an Islamic empire in the Middle East now control yet another powerful economic weapon – wheat supplies. Fighters from the Islamic State have overrun large areas in five of Iraq's most fertile provinces, where the United Nations food agency says around 40 percent of its wheat is grown. Now they're helping themselves to grain stored in government silos, milling it and distributing the flour on the local market, an Iraqi official told Reuters. The Islamic State has even tried to sell smuggled wheat back to the...