As vehicle attacks rise, an ordinary object becomes an instrument of fear

Years of research has found that fear can eventually divide and poison societies

This time it was Barcelona. An ordinary van was transformed into a deadly and indiscriminate weapon.

It seemed to be yet another blow to trust in a basic social compact: that people are essentially safe when they walk down the street, relying on drivers to at least try to follow the rules. That accidents would be impersonal and random, and that everyone would try to avoid them.

Even though the automotive terrorist attacks of the past two years are far rarer than accidents, they are a warning that a driver can wield the ordinary car as a weapon. If anything — even