Courage under fire.
From the New York Times
In one widely recounted incident, a force of about 20 guerrillas charged a Marine armored patrol head on. Only about eight survived the first devastating round of fire, but they got up and charged again.
This is an ominous sign. To the historian, such behavior brings to mind the ever-present banzai charges in the Pacific campaign of WWII. This type of tenacity, of course, made invading and assaulting Japan so distasteful that the decision was eventually made to use atomic weaponry. I cannot imagine the same result here, but it is likely that such attacks--as well as less dramatically courageous guerilla action--may spur commanders, if only locally, to indulge in a less soccer-mom-friendly mode of warfare within populated areas. This in turn, historical example suggests, can lead to increased antipathy towards U.S. forces from the local population.
Striking a balance between maintaining certain moral standards and successfully fighting a war is as old as war itself. There are no simple answers for Gen. Franks and company. However, it would benefit this country on a great many fronts to be able to capture not only Baghdad but the moral high ground as well.