‘Does the pin make me go ?’ Like most 16-year-old British schoolgirls, Safaa Boular was adept at using emojis. She wanted to ask her online mentor if, when she detonated a bomb belt, she could be sure of killing both herself and her target. Safaa was a fast learner and, before too long, was planning to involve her older sister and her mother in an attack on the British Museum, among other targets.