There's a reason we're not sending more troops to Iraq or Afghanistan. We're doing all we can just to keep up with the current rate of deployments. While our military is a perfect size to knock out other militaries and governments, it's simply not large enough to maintain long term, large scale occupation duties.
Rummy has resisted increasing the size of the Army because he is enthralled with the arguments of the "transformationists". Part of the way that he is trying to address this problem is in how he has reorganized the Army into brigade combat teams. This is a good reform, but we probably should have added another 100,000 actives to the Army and Marines after 9/11 (and provided whatever incentives needed to get up to that strength). It doesn't help that it often seems like he is playing chess without looking at the pieces.