I don't see how removing the Secretary of Defense helps either the country or the Republicans, especially given the pre-election vote of confidence in his full tenure. He was on the right track reforming the military; the removal of the Taliban and the three-week victory over Saddam were inspired.
So we are down to his supposed responsibility for the later effort to stop the 3-year plus insurgency, whose denouement is not yet known. Rumsfeld's supposed error that drew such ire was troop levels, i.e., that he did not wish to repeat a huge presence in the manner of Vietnam, but sought to skip the 1964-1971 era morass, and go directly to the 1972-5 Vietnamization strategy of training troops, providing aid, and using air power.
Y'know, for a bunch for whom any comparison of a certain SE Asian nation with our glorious Iraq adventure was tantamount to treason just four years ago, the Right sure keeps bringing the subject up these days. Hanson, here, is somewhat less disingenuous than the rest, maybe because of that part-time gig as a military historian, albeit one whose primary goal these days seems to be finding moral lessons for children among history's carnage. So this time we will lead off by not even mentioning that Professor Hanson passed up his opportunity to get his military history first-hand; in the long run his pursuit of an advanced classics degree just made Vietnam that much more meaningful for the rest of us.
We can't really argue directly with what little is actually said about Vietnam above. Okay, Nixon's so-called Vietnamization was supposed to be the policy we were pursuing all along, but that's small beer. Instead it's the interesting mirror-reversal at work here: Rumsfeld is defended as having sidestepped the "Morass Phase" of Vietnam, except he does so in a war he and all the other war buffs kept telling us was nothing like Vietnam. (Reminiscent of Our President's renewed effort to get Congressional approval for actions he claims don't require it.)
As I've said once or twice before, the "Rumsfeld Doctrine" stuff is just bunkum. We went into Iraq with 150,000 troops because that was all we could muster without a draft, a massive reorganization of existing military obligations, and/or an Afghanistan-style international alliance, and any one of those would have required a delay of at least a year. And that delay a) would have demonstrated that Iraq was no threat, nuclear or otherwise; b) would have allowed the hated Europeans to broker a peace that did not give George W. his chance to out-manhood his Daddy; and c) did not fit in with the reelection scheme, which is how this thing began life in or around the summer of 1999. A draft would have taken about 18 months, plus it might have been so enormously unpopular as to stop the war in its tracks altogether. A large international force might have been assembled for fall of 2003, but these guys weren't really interested in coalition building, since the base is still feeding off the Birch Society anti-UN paranoia, as anyone who might have casually mentioned an international coalition in their hearing back in '02 can attest.
So spare us the "remarkable three-week victory over Saddam" bit. That was the world's only superpower scraping up the rusting remnants of a once fifth-rate power. It's like saying Hitler deserves credit for making such short work of the Poles, if only his later actions hadn't hit a minor snag a little farther to the east.
That occupation, or failure to even have a plan in place to conduct one, is Rumsfeld's legacy in Iraq. The actual battle, such as it was, we'd been wargaming for twenty years. Let's remember that an insurgency is not exactly an unknown tactic sprung on us for the first time. This was precisely one of two potential threats (other than there actually being WMDs) any military historian could have foreseen: an insurgency using small arms and improvised weapons, or turning Baghdad into Little Stalingrad. And let's not forget what Rummy said about the nascent insurgency at the time: "[A] mixture of a small number of terrorists, a small number of militias, coupled with some demonstrations and some lawlessness." None of which the Pentagon was prepared to deal with.
And it's not just because we went to war on the cheap and in a hurry. Army commanders reported being unable to plan even the basic make-up of postwar units because the Pentagon offered no direction, and because bad news got put on hold for months at a time in hopes that something would turn up and magically turn things around. That is not entirely Rumsfeld's doing--you can lump Cheney, Rice, Perle, and Feith, and the President, assuming he was paying any attention, right in there with him--but the Pentagon was responsible for day-to-day operations. And they were less than a failure. They were criminal.
One more thing--you'd think a military historian might have, by this point, tumbled onto some of this. Maybe realized that the latest episode of Jim Baker pulls his old boss' kid's nuts out of the fire again includes actually talking with commanders in Iraq and finding out just how badly the civilian leadership has screwed up. For the life of me I can't figure out who guys like Hanson think they're hiding the truth from anymore, unless it's themselves.