Another thing that commentators love to harp on, and have done so much more since September 11, is moral relativism. The argument is basically that moral relativism means a person is unable to tell the difference between right and wrong, and therefore anything anyone does is perfectly ok.

But what moral relativism really is is a tool to allow us to make the philosophical distinction between what people should do and what people do do. By allowing us to set aside moral judgements (which tend to stop investigation -- "that's wrong, end of story"), relativism permits us to dig deeper into the causes and motivations of things that have happened. The purpose of this is not to excuse things, but rather to understand why they happened and therefore allow us to project the consequences of our future actions.

Just because something's wrong doesn't mean people won't do it again. You should be able to walk through a dark alley with $100 bills hanging out of your pockets. But I'd rather avoid dark alleys than get mugged in one and take self-righteous solace in the fact that the mugger is to blame.