3 ms·

I thought the figure provided was the marginal cost.

• mikeash 10y ago
  It is, of course. Nobody is calculating the cost of the war as the defense budget multiplied by the time. The cost includes about $750 billion in direct appropriations for the war itself (separate from the overall defense budget), plus numerous indirect costs such as additional medical care and disability payments to veterans, replacement of destroyed equipment, and interest payments due to increasing the national debt.