The financial cost of war is often little more than an afterthought, but President Obama’s decision to take several months to announce his decision on the Afghanistan escalation has allowed people to ask, what will this cost?

The answer seems to be: depends who you ask. The Pentagon is estimating around $500,000 per soldier, per year. The White House estimates that it’ll actually cost about twice that much.

The matter is contentious, but officials in both camps say the price “could change “over time, and in matters military that almost always means “could go up.”

Considering the hundreds of billions of dollars already spent, these numbers may not seem like much. But with 30,000-40,000 troops each costing so much and all staying for an unknown number of years, it will rapidly add up to a bill that the Obama Administration, whose military budgets going forward foresaw a significant drop in the cost of overseas adventures, hadn’t prepared for.