While it's just a drop in the bucket compared to the $4 to $6 trillion price tag of the 2001 war in Afghanistan and the 2003 invasion of Iraq, fighting ISIS isn't cheap. A new estimate places the annual cost of the war on ISIS at about $40 billion a year, a figure that will certainly rise if the effort is expanded beyond airstrikes.
That $40 billion will be added to the Pentagon's 2015 budget of $496 billion, plus its $58.6 billion "Overseas Contingency Operation" fund to pay for America's various Middle Eastern entanglements. Meanwhile, more than $90 billion has been spent in the still-active war in Afghanistan this year, even as a majority of Americans now believe that war was a mistake. Bonnie Kristian