So why has there been such an overreaction [to 9/11]? Unfortunately, the commentators who detect one have generally explained it in a tired, predictably ideological way: calling the United States a uniquely paranoid aggressor that always overreacts to provocation.
And maybe the reason for that is that the US has not in contemporary times (with contemporary weapons) had a war fought on its shores, and so its citizens are probably insulated from just how terrible war is.
Anyway, read the rest of the article. It's quite insightful.