Their concern over a liberated Iraq could be as simple as making sure that the US doesn't have access to the fuel to drive out culture. Iraq, furthermore, is a lot easier to get into and out of, as the physical problems of the Hindu Kush do not apply as they do in Afghanistan.

I do think that geographical position is another of the unstated reasons why the US invaded Iraq. Iraq is easier for the US to resupply than Afghanistan, and easier for US forces to get around in. There's no terrain for the foreign jihadis to hide in - no mountains as in Afghanistan, no triple canopy jungle as in Viet Nam.

With US detection equipment, any infiltrators day or night can be easily spotted crossing a border, whereas crossing into Afghanistan in the shadow of the Hindu Kush will shield an infiltrator from electronic surveillance.

US presence in Iraq is something that al Qaeda and their ilk cannot afford to ignore. Not only is it a Muslim country, but it is also the ancient capital of the Caliphate. You are right that they fight us there because we weren't there before. In Iraq, we are on the strategic offensive, but the tactical defensive.

This is the ideal state. Remember that Robert E. Lee was called the King of Spades by his men early in the war, due to his fondness for entrenching. His greatest blunder was going on the tactical offensive on day three at Gettysburg.

However, the clock is running out in Iraq in my estimation. In the absence of decisive action by the US, the enemy will regain the strategic initiative within Iraq. Sadr's Mahdi army is being ripped to shreds as I type this, but I believe this was simply a probe by the Iranians. They've not yet activated their assets in the SCIRI, nor have we seen much evidence of Hizbollah or Imad Mugnyia. More fearsome combat in Iraq will follow this year, and will continue until the next stage of the war on terror begins.