Troll,
I'm not at this point questioning whether you should have gone in or who is killing whom. I'm assuming that in these sort of exercises, say, a plane hijacking where a gunman is holding 200 people hostage, the persons who are going in calculate the likely casualties from all causes. And then decide if to go in by force or try some other method. In the plane scenario, for instance, it wouldn't make sense to risk letting the hijacker kill 180 to save the other 20.

All I'm asking is how many casualties the USA would consider acceptable (for want of a better word) in return for toppling Saddam. If 5000 is the figure, so be it.