Repeat: you don't shoot at people to encourage them them to slow down.
Not any more than you chase someone while waving a large stick and yell, "Stop!" if you only want to talk to him.
There is something wrong with a procedure that results in so many friendly and neutral people being killed. "Oh, well, that's war for you" is not sufficient.
How are the soldiers who shot at a hostage being told to deal with it? To tell themselves that the Italians deserved it because they didn't read American signal displays correctly? If it had been Iraqi soldiers shooting at Americans, what would you be saying then?