In defense of racial profiling: Daniel Drezner quotes an article from the Persian Mirror arguing against the racial profiling of airline passengers,

Even within the Arab community, should there not be a difference between a Saudi, an Egyptian, a Jordanian, a Kuwaiti, or an Iraqi? How do we profile them? Instead of trying to make the world a Mickey Mouse Park where things fit neatly into boxes and security agents can pick and choose terrorists with color-coded instructions from the government, shouldn't we put some real brains behind the plethora of terrorist networks that continue to terrorize our daily activities all over the world?

This echoes an argument I've heard from many liberals: "instead of racial profiling, lets do X." But its a false dichotomy; there's no reason why we can't fight terrorism with racial profiling and do X.

Race, sex, religion, and sexual preference all contain information - information that is useful in predicting how likely a person is to hijack a plane. Its difficult not to feel squeamish about using this information, but I don't think we can afford to ignore it in the post-9/11 world.