Right now the big terror threat comes from radical muslims from foreign countries, however we don’t know if that will be true in ten years. Maybe in ten years it will come from white Eastern European anarchists, or Chinese Falun Gong, or South American fascists - the point is nobody can predict the future, and even with profiling you can’t predict who a terrorist is or isn’t 100 percent of the time. We need systems that don’t care but that will always flag explosives.