"Congress would actually have to have a vote to authorize it and they would have to jack up the budget," he said. "I don't think the politics on this are at all clear right now and won't be for another week or two."
He added, "The money issue has not been addressed in the Congress at all."
If the government finances this chapter of U.S. military intervention in the Middle East the same way it's financed the Iraq and Afghanistan wars, it will simply add the cost to the nation's credit card. George W. Bush was the first president since World War II to use deficit spending to cover the cost of decisions to invade Iraq and Afghanistan after the September 11, 2001, terrorist attacks.
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That added about $1.5 trillion in military costs to the federal debt over the subsequent 13 years – and prompted some liberal Democrats, including former House Appropriations Committee Chairman David Obey of Wisconsin, to call for a special "war surtax."
The surtax would be "a percentage of your tax bill," Obey explained in 2007, according to CNN. "If you don't like the cost, then shut down the war." The measure would have required low-income and middle-income taxpayers to add 2 percent to their tax bill, while higher income taxpayers would pay an additional 12 to 15 percent.
The idea never gained traction – and won't this time either. Congress is in no mood to raise taxes before a crucial November election that will determine the political control of the House and Senate. What's more, the cost of expanding military action against ISIS is unlikely to be onerous compared to the overall $4 trillion federal budget – at least early on.
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"I don't think you put on a surtax every time there is a short-term bubble in policy change," Obey said in a phone interview Tuesday. "But if it were to go on for a significant amount of time, people ought to take a hard look at it."
Obey added, "We're going to pay a price for years because we didn't have a war surtax to pay for Iraq and Afghanistan. But I think there's probably a very large difference between the magnitude of the cost then and the cost now."
—By Eric Pianin, The Fiscal Times