With the United States now engaged in military operations against the Islamic State of Iraq and the Levant (ISIL), there are many questions regarding the cost, duration, and scope of these operations. This CSBA Backgrounder provides a range of estimates for the cost of military operations against ISIL to date and how much these operations may cost over the coming months.
Bottom Line Up Front
The cost of U.S. military operations against ISIL through September 24 is likely between $780 and $930 million. The cost of future operations depends primarily on how long operations continue, the intensity of air operations, and whether additional ground forces are deployed beyond what is already planned. Assuming a moderate level of air operations and 2,000 deployed ground forces, the costs would likely run between $200 and $320 million per month. If air operations are conducted at a higher pace and 5,000 ground forces are deployed, the costs would be between $350 and $570 million per month. If operations expand significantly to include the deployment of 25,000 U.S. troops on the ground, as some have recommended, costs would likely reach $1.1 to $1.8 billion per month. On an annualized basis, the lower-intensity air operations could cost $2.4 to $3.8 billion per year, the higher-intensity air operations could cost $4.2 to $6.8 billion per year, and deployment of a larger ground contingent could drive annual costs as high as $13 to $22 billion.