There has been some revealing new information coming out recently regarding the strategy against ISIS. One aspect many find troubling is the apparent failure of U.S. and coalition forces to sufficiently target and destroy oil infrastructure located in ISIS territory, which accounts for a significant portion of the terror group's annual income. The argument goes, if we want to impact their operations, we should target their primary sources of income, and choke off their operational funds. So, why does ISIS oil infrastructure still stand? Is this the result of an intelligence failure? Negligence? Or, is there a more purposeful reason?