Casualty numbers include more than KIA. They also include wounded. Right now, we've had about 7000 injuries to soldiers, ranging from John Kerry-types all the way to seriously debilitating. I don't think all those soldiers have had to leave Iraq, but you can't simply drop new guys into a unit.

All of this degrades the fighting capabilities of a division, and if we are planning anything against Iran (preferably) or Syria (less-preferably) for after the election, we had better well have both those divisions, as well as whatever else we send in, at full readiness, strength, and cohesion.