The White House doesn’t know yet how much the new war with ISIS will cost, but it knows how it will pay for it: the all-purpose war funding credit card.  

Officially known as Overseas Contingency Operations, it’s the catchall account used to fund the Iraq and Afghanistan wars that is now funding the war against the group also known as the Islamic State or ISIL.  

The White House is counting on OCO money in the pending continuing resolution to pay for President Barack Obama’s plan to go on offense against the group.  

In a practical sense, a vote for the CR is a vote to fund Obama’s war, even though the words “ISIS” and “ISIL” do not appear anywhere in the text. In the draft House CR, it’s simply listed as funding for “Overseas Contingency Operations/Global War on Terrorism.”
The White House is confident the OCO funding included by House Republicans in their first CR draft will be enough for now, because the drawdown of troops in Afghanistan has created room for more war spending somewhere else.  

Obama had requested a sharp cut in the OCO — from $85 billion to $58.6 billion in the upcoming fiscal year starting Oct. 1 — to reflect the drawdown in Afghanistan, but the CR funds OCO at the $85 billion level. Bottom line: It makes billions available for the new war .  

So far, the White House hasn’t come up with a ballpark figure for how much the effort will cost, or at least it hasn’t given that number to Congress or to CQ Roll Call.  

It certainly will be hundreds of millions of dollars a month — given that the operation was already costing $7.5 million a day through August, before the president dramatically escalated the mission. But there’s the potential for it to cost much more, although one would expect the lack of a ground invasion to reduce costs significantly relative to the earlier Iraq and Afghanistan invasions.  

The White House hasn’t ducked the “war” word — Press Secretary Josh Earnest acknowledged the United States was “at war with ISIL” on Friday. But he was just as insistent in noting that it will not be like the previous Iraq War, and reiterated that no ground forces would be engaged in combat.  

Congress and the White House instead have been focused on a fairly cheap part of the new war — a $500 million fund, which would also be paid for by OCO, for training and equipping Syrian rebels. While Obama has claimed authority to attack ISIS based on the 2001 war authorization after 9/11, an authority some lawmakers dispute given ISIS did not exist then, the White House has said it needs Congress to approve so-called Title 10 authority to train and equip the rebels.  

Gordon Adams, who was in charge of national security budgets at the Office of Management and Budget during the Clinton administration, told CQ Roll Call he thinks the total costs could potentially hit $1.5 billion a month. That’s about the size of NASA’s budget.  

Adams said he believes air operations in Iraq and Syria could cost $10 billion over the next year, assuming this war lasts that long. Other costs, including training, supporting and equipping “Iraqi forces and Syrian rebels,” could total another $6 billion to $8 billion a year.  

Lawmakers are eventually going to want to hear a price tag from the White House.  

“Obviously, my constituents care a great deal how it’s paid for,” said Sen. Ron Wyden, D-Ore. “I was one of 20-some in the Senate who voted against going to war in Iraq and hardly a week goes by when people don’t come up and say ‘You know, I sure wish we had that sum.'”  

Sen. Richard J. Durbin, D-Ill., who chairs the Defense Appropriations Subcommittee, said it’s too early to speculate how much the war will cost.  

But Durbin told CQ Roll Call a vote for the Title 10 authority to equip and train the Syrian rebels would be a vote for war.  

“People know what they’re voting on here. I do,” he said Thursday. “If I want to make the argument, ‘Oh, it was stuck in the back of the bill, and I never got to that page.’ Try to explain that back home. Folks will remember how you voted on that issue.”  

Senate Appropriations Chairwoman Barbara A. Mikulski, D-Md., also suggested there should be limits on the war.  

“Defeating ISIS will take time, but we cannot have an open-ended conflict. We must avoid the mistakes made following 9/11. There can be no blank checks and no proposals without real strategies connected to them,” she said in a statement Thursday.  

The OCO account has never actually had a dedicated funding source. Every dollar for it has been borrowed.  

Some Democrats proposed a war tax during the George W. Bush administration so that future generations wouldn’t have to pay for this generation’s wars — but that proposal went nowhere.  

In recent years, lawmakers — and the president — have regularly proposed raiding OCO as a budgetary piggy bank — from rolling back the sequester spending cuts to increasing spending on highways and bridges. But budget hawks have ridiculed those proposals as gimmickry, especially given that the OCO request was paid for with borrowed money in the first place.  

The group Taxpayers for Common Sense has labeled the account a “slush fund” because it is not used solely for war costs. On Monday, the Department of Defense proposed using more than $1 billion from OCO to buy eight F-35s for the Air Force and Marine Corps.  

Niels Lesniewski and Megan Scully contributed to this report.    

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