Returning home one spring five years ago from a secret visit to Beijing in his armored, fully wired train car, North Korean leader Kim Jong Il got an unnerving, firsthand demonstration of the potential downside of technology. A huge explosion ripped through the Ryongchon border station, and some officials initially thought it was an assassination attempt triggered by a cell phone. As it turned out, the fireball was more likely the result of two trains’ colliding nearby, possibly as a result of miscommunication about changed schedules stemming from Kim’s clandestine travels
