The Iraq War should have made this obvious, if it wasn't already. But Rumsfeld was dogged in his commitment to his vision and had a distorting effect on the debate. The more the left attacked him — often unfairly — the more the right rallied to him, and for the longest time it was, weirdly, liberals calling for more troops in Iraq and a bigger military and conservatives denying the need for the same.
As it became increasingly clear that more troops were needed in Iraq, it could be plausibly (if not correctly) argued that the troops weren't available. Thus, Bush was in an extraordinary fix for a conservative Republican — his ability to win a major war was arguably bounded by his own underfunding of the military.
Rumsfeld's departure has broken the ice. Liberals and conservatives are back to their natural positions on the troop surge to Baghdad (against and for, respectively). The military brass, who aren't very good at speaking truth to power, have adopted a new urgency of tone in public statements about shortfalls in manpower and equipment now that they know they have a receptive ear from new Secretary of Defense Robert Gates.
The Bush administration wants to add roughly 90,000 to our ground forces over the next five years. It probably should be as much as double that, and happen faster. Bush's latest proposal for the Pentagon would hike military spending to only 4.2 percent of the gross domestic product, well below the 9.5 percent of the Vietnam War and beneath even the 4.7 percent with the Carter Administration.
Given the threats we face and the ground to be made up, spending should be about 5 percent for a long time to come. If a president must ever again do a Nixon-to-China on military spending, let it be a liberal Democrat gladly giving the military all that it needs.