Wonsan: At the turbine hall at North Korea’s Wonsan Number 5 hydropower station, a placard mounted on a wall proclaims: “Prosperous and Powerful Nation”. But when it comes to electricity the North is anything but. The country has made rapid progress in its weapons programme under leader Kim Jong-Un, detonating what it said was an H-bomb last month and launching intercontinental missiles that apparently bring much of the US mainland into range.