I saw a blog entry that had a good analogy of this mess.
Imagine a patient in the Intensive Care Unit at a large hospital. The patient had a complex surgical procedure, against the advice of many skilled surgeons, involving a high powered, but no so good, surgeon, and numerous assistant surgeons with whom he's in partnership, and there was a major medical error during the procedure. The patient, still alive, was taken to the ICU on life support, including pulmonary support and blood transfusions, but will die if taken off the intervention.
In Iraq, Bush is the surgeon who made the error, oxygen is the money being spent on the "patient", and the "Blood transfusion" are the lives of US government soldiers going inharms way and not surviving, one by one, month by month.
Bush isn't being affected by his malpractice, nor the cost of the "blood transfusion" being given, and maybe increased, this year. Bush doesn't want the patient taken off life support because he doesn't want to face the consequences of his actions, his malpractice.