Hmm. The past debate that went on between advocates of the "Afghanistan option'" in Iraq of relying on special forces backed by air power to stiffen local forces and advocates of heavy armor in a conventional invasion has long been over. We will go in heavy. This is good, but given that the large bureaucracy that is the Pentagon is in charge (and I say this not as an insult but as a fact of life), I think we will see the Afghanistan option in Iraq even as we drive on Baghdad with an overwhelming American conventional force.
But the Afghanistan option will be not against Saddam's regime. It will be directed against the al Qaeda-related thugs holed up in northern Iraq. The Kurds will provide the local infantry for the quantity and American and allied special forces will provide the Kurds with an air force. Tenth Mountain and probably British 16th Air Mobile Brigade will provide the backbone of high quality and highly mobile infantry to go after the bastards. The Kurds will be retaking their land and won't have to go up against heavy armor and artillery so their full cooperation is likely. Yet, retaking their land is their objective. Killing the Islamists once they break will be up to the American and allied special forces and leg infantry. That too is a lesson of the Afghanistan option.
And talk about linking Iraq and 9-11. Who will be able to complain about our invasion 'distracting' us from finishing off al Qaeda when we will be going after these thugs in a major way? Indeed, without a major invasion to take down the Saddam regime, sending in anybody after the Islamists would be too risky. Were I Saddam, I'd (in addition to shaving the cheesy mustache) risk a whole corps of Republican Guards and even more regulars to launch a thrust into Kurdish areas to hit American light infantry. We'd need heavy air power to hold them off and would suffer heavy casualties even in a successful defense. We might have to pull them out giving Saddam's regime a crucial victory over us.
No, such an effort against terrorism requires an invasion too. The main effort goes into western Iraq in order to drive on Baghdad from the west with XVIII Airborne Corps (2 heavy divisions with 6 brigades plus 101st Airborne and perhaps a Marine brigade). A feint to draw Iraq's attention by simulating the main effort with a fake V Corps will advance north out of Kuwait (1 heavy division with 2 brigades as the core plus attack helicopter units). And to round out the invasion, there will be a British/Marine Corps drive into the Basra region (and then north to Baghdad with the rump V Corps to support the main effort to reach Baghdad and take down Saddam's regime). The Northern Front will be separate from the southern and western thrusts with a different objective: al Qaeda-related terrorists.
The conventional generals and the snake eaters each get to do what they do best in ways that both support American interests.