The American invasion and occupation has been seen by many (not to say most) Iraqis as an extreme form of insult against their dignity. Remember that the American forces had no qualms about displaying the captured Iraqi president in a painfully humiliating light; no matter how Iraqis hated Sadaam, seeing him mocked in this way by an invading nation was a blow to their national pride.
Given this background, and that the mastermind of this national humiliation shows up on their soil and stages a little media event as a capstone to his “liberation of the Iraqi people”, how outrageous is it, really, that someone would show less than decorous respect?
Imagine that some other country overran the US to liberate us from the evil Bush, leaving us with hundreds of thousands of dead and a non-functional government. Then the great leader of our “liberators” comes to New York to gloat a bit. Shoes, anyone?