Your comment is a quote from the snopes.com website. I think their article on this video is quite fair.
I seem to remember something from my military days about the geneva conventions.
I seem to remember that they were pretty clear about the fact that you are not supposed to shoot the wounded.
It seems to me that if a tape like that surfaced where some Republican Guards shot a US GI and then said, "he's wounded, get him," and killed the wounded American, there might be just a bit of outrage circulating on this board about the "savagery of the terrorists."
If one wants to claim one has the moral highground, then I think one has to be pretty meticulous about following the "Rules" of war--even if that is an oxymoron.
If one reads Ambrose, one finds all sorts of incidents discussed where German and American GIs didn't shoot wounded, didn't shoot medics, etc.