The hard questionsNorth Korea is providing us with an advanced showing of the next stage in global nuclear blackmail: the fruits of nuclear proliferation, a process which began in the 1950s, but which is now beginning to run out of control.Here is a state in a condition of economic desperation, due to its past follies, threatening to start a war – a nuclear war. That is, unless it is propped up, presumably indefinitely, by enough food and oil to keep its ruined economy from collapsing and its co…