Ongoing operations in Iraq and Syria to confront the extremist group calling itself the Islamic State cost an estimated $7 million to $10 million per day, the Department of Defense said Tuesday.
"We're still at the $7 million to $10 million, and as I said when I talked about it last week, it's just an estimate and it's likely to change over time," Pentagon spokesman Rear Admiral John Kirby told reporters. "And as operations intensify, you know, you can expect that that number will probably go north of that over time."
Earlier Pentagon estimates had put the cost of fighting the Islamic State, also known as ISIS or ISIL, around $7.5 million per day, amid the US escalating its campaign in Iraq with airstrikes beginning in early August. Since the stepped-up involvement in early June, including surveillance flights and increased deployment of military advisers, the number was much lower.
Rear Adm. Kirby stressed that the $7 million to $10 million figure is "only the best estimate" at this point, and the number could be revised higher. The US is on its 10th day of airstrikes in Syria, and has on certain days conducted double-digit airstrikes against ISIS targets. The Obama administration has indicated the fight to "degrade and ultimately destroy" ISIS could take years. According to the Pentagon, ISIS has an operating range between 20,000 to 31,000 militants within the region.
How far upward that figure is revised could depend on whether the scope of operations is expanded even further. According to a report released this week by the Center for Strategic and Budgetary Assessments, the high point for annual costs of the fight against ISIS is around $22 billion — if airstrikes expand further and a significant ground force is required.
Here's a map from the CSBA report that breaks down the cost of various aircraft involved in the operations:
Thus far, the US has led more than 200 airstrikes against ISIS targets in Iraq, and another 60 strikes with coalition forces in Syria.
Several attacks were aimed at destroying 12 ISIS-held Syrian oil refinery targets in hopes to disrupt the extremist groups ambitions of selling crude oil on the black market. In that particular airstrike, Rear Adm. Kirby announced 16 fighter jets participated with the majority of bombs and jets belonging to allied forces.
The United Kingdom is the newest ally to join the coalition and has flown approximately 30 reconnaissance missions over ISIS territory. Earlier this week, the British Defense Secretary Michael Fallon announced that the Royal Air Force flew a successful mission and destroyed ISIS military equipment, the Telegraph reports.
With the US Air Force taking the led out of the sister service branches, the Navy has currently spent roughly $100 million on campaign operations.
“Most of the Navy and Marine Corps missions were at the beginning because we were there, but as the campaign has gone on, I think the Air Force announced yesterday they have done about 75 percent,” Navy Secretary Ray Mabus said.
Since President Obama has stressed he will not deploy US ground troops into combat situations in Iraq or Syria, higher-intensity air operations in Iraq and Syria could end up costing $4.2 billion to $6.8 billion per year, according to the report.
The Pentagon has said that financing for the ISIS fight will come from the Overseas Contingency Operation fund, an account exempt from budget caps that was created for the wars in both Afghanistan and Iraq last decade.
Earlier this year, Obama sought to dwindle the budget for that account down to about $59 billion from $85 billion, reflecting the decline of operations in Afghanistan. But the spending bill passed by Congress last month continues to fund the OCO at the $85 billion level.