Why are so few people talking about the eruption of sexual violence and harassment in Europe’s cities? No one in a position of power wants to admit that the problem is linked to the arrival of several million migrants—most of them young men—from Muslim-majority countries.In Prey, the best-selling author of Infidel, Ayaan Hirsi Ali, presents startling statistics, criminal cases and personal testimony.  Among these facts: In 2014, sexual violence in Western Europe surged follow