"Dimitri Bontinck lived every parent's worst nightmare. His teenage son, introduced to Islam by his girlfriend, fell into the clutches of a radical mosque. Dimitri watched helplessly as his son, Jay, transformed from a gentle boy to a soldier in training, wearing traditional robes and following a strict diet. Completely brainwashed, Jay snuck out of the house and traveled to Syria, all but vanishing. Too late, Dimitri learned that their country, Belgium,...