LIVING WITH PROFILING: David Gelernter asks good questions:

Are we eager enough to prevent the crime in question to stop people (like bulky-backpack wearers or travelers who appear Middle Eastern) who we know might be guilty but almost certainly aren't? Are we willing to impose this inconvenience on innocent people who fit the profile to find a few guilty ones? If the goal is to pre-empt "ordinary" crimes (theft or robbery) that hurt only a few individuals, the coldblooded answer is probably no. If the goal is to pre-empt a terrorist attack that might hurt the nation, the answer ought to be yes.