A donkey cart, a mailbox, a garbage bin, a package delivered to the office, a letter, a suitcase, a car, a truck, an airplane, a subway carriage, a dog, or a human being can be harmless objects in themselves. Yet recently each has been used by terrorists as a container or projectile that caused human suffering, injury, or death. Moreover, the presence of these items in everyday life in Western civilization is as natural and unobserved as the glass in our windows.