Some people (it was argued) are obviously not terrorists: newborn babies for example. And nuns. Nuns are mild, gentle people who wouldn’t say boo to a goose, let alone blow up a plane. They can be safely waved through after only the most cursory of searches. That was the view of one of the speakers.

But somebody else thought nuns should be regarded as prime suspects, because what could be more fundamentalist than a nun? Nuns believe so strongly in the truth of their religion that they dedicate their whole lives to it. They live in like-minded communities, and spend many hours in rituals of religious devotion, serving a god who, they believe, has a special mission for them – their vocation. A god who, if they follow their vocation obediently will reward them with eternal bliss, but who, if they don’t, may send them to hell.