“In the year since ISIS leader Abu Bakr al-Baghdadi declared a newly found Caliphate, the U.S. has spent at least $2.4 billion to beat back extremist organization while the group grows its coffers, territory and military prowess. That comes out to about $9 million a day. And the total price tag is bigger than the World Bank estimate of Afghanistan’s 2013 GDP.”
Source: ISIS By Numbers: High Cost Of Fighting World’s Deadliest Terrorists