Senator Rand Paul said the other day, after refusing to be physically searched at an airport, that the TSA should ignore 8-year-olds from Bowling Green because it's the 8-year-olds from Kandahar that are blowing things up. This statement was never about logic, since there are lots of prominent folks from towns like Bowling Green who have done much to harm Americans (see Timothy McVeigh or Ted Kaczynski).
What this really is about is the Other. It's a natural psychological response to look at the world through simpler lens when people are under duress. One of the ways that our lens get simpler is to group people into broad categories of "us" and "them." Then while the lines between the different people among the "us" start blurring, so do the lines between the different people among the "them," but then at the same time, the line between "us" and "them" starts to firm up. What was once a mixed and diverse group of people gradually morph into two divergent groups with increasing homogeneity.
For Senator Paul, the boy from Bowling Green is a representative of the "us." For the most part, the members of "us" are not dangerous to the rest of us, but for Senator Paul, the few dangerous ones fade away until all of "us" are non-threatening.
The boy from Kandahar on the other hand is one of "them" and not to be trusted. All of the non-threatening folks among "them" fade away into they all look threatening. It's easy to see why Senator Paul suggests that they are the only ones TSA should mind.
This splitting up of all people into two teams in our mental frameworks has its merits. When there's a threat, and one has to act quickly, it's good to classify people in the simplest possible scheme, and a 2-classification scheme is about as simple as it gets. Unfortunately, as in sports teams, people in real life don't always wear one of two team uniforms. So it helps us to use something other than uniforms to tell the teams apart... nationality, religion, ethnicity, etc.
This was never about logic. It's always a mechanism for people to feel comfortable with how they see the world. Too much complexity can make it difficult to decide what to do. Simplifying the world makes it easier to deal with, even if the decisions made end up backfiring.
