I recently saw in the news that the Iraq War casualty count for US forces has now exceeded 4,000 killed (Broken link, active March 28, 2008). This is tragic, especially for the families of those 4,000. But the media has lost the perspective of history. In the Battle of the Bulge during World War II, when Allied forces were advancing across France, over 19,000 US soldiers were killed in the course of the battle, and the vast majority of those were within the first three days! That is from only one battle out of the entire war. While that is a huge amount of loss also, it is barely a drop in the bucket compared to the warfare of medieval or ancient times.
I think that today we have such little patience for casualties, setbacks, or changes of strategy, because most of us (including the media) know so little history and therefore have no frame of reference to compare actually how astonishingly well we are doing in Iraq.