While personally I don't think causing, much less celebrating any beings' suffering is a good thing, I'm going to stick my neck out and say that across the world there were many people in many cultures who felt the US had crossed many lines for many decades and had something coming to it. The normal Palestinian people feel the brunt of immense US support for Israel on a daily basis and it is understandable within that light that this rare event gave rise to celebration.
I will also point out that you used the phrase "the TV showed" ... if you look up influences on and historical bias of US television networks, the net change in US international military presence after the event you may find more than one way to explain the visions the US population have been and continue to be spoonfed through the likes of CNN, Fox News, certain computer games and the US military heroism of Hollywood, which are so predictably brought out every time certain topics are discussed.
