North Korea rarely airs its dirty laundry in public, but Kim Jong-un’s latest purge of a senior military official was staged for maximum visibility – a warning, analysts say, to generals growing too comfortable with their expanding economic power that they answer to him alone. “Kim is effectively telling military and party leaders: ‘Don’t even think about it. You are under round-the-clock surveillance,’” said Yang Moo-jin, a professor at the University of North Korean Studies. On Friday, Kim...