When Islamic State seized Iraq’s largest northern city of Mosul almost a year ago, tribal leader Hekmat Suleiman was sure the extremist militants wouldn’t expand further into his hometown. “We bet Islamic State won’t have what it takes to last,” Suleiman said in October during a visit to the Iraqi Kurdish city of Erbil, smoke rising from his shisha water pipe. “We’ve reached the beginning of the end of extremism.” He was wrong. His hometown of Ramadi fell last month, three days before Islamic State captured Palmyra , a 2,000-year-old UNESCO world heritage city on the Syrian side of its territory. The battlefield victories ahead of the first anniversary of the group’s self-declared caliphate on June 29 emphasize its ability to endure U.S.-led coalition airstrikes as well as lower oil prices, […]