The answer from the administrations (Bush & Obama) has been, yes it is worth it.
The rest of the world are seeing the implications of this kind of warfare and its result.
The short-sightness of the Bush administration is a disaster. In a single blow, the free world lost the majority of it's ethical and legal arguments due to this whenever it comes to totalitarian regimes and their actions.
For 2000 americans murdered and that is nothing and I dont mean to be offensive but on a grand scale that is nothing compared to what happens around the world and what the US itself as others try to stem.
It just makes me freaking sad and upset to be honest.