What the world seems to forget is that during the Korean War in the 1950s the USA blitz bombed North Korea (much as it did in Vietnam a decade later) and this is why the Koreans display such fear, paranoia and hatred towards the US. Yes, I'm aware that 'they' started it by invading the south, but was still a horrendous overkill.
It is the memory of this that has led to the development of nuclear weapons by the current dictator.
Why can't these fears be allayed by a Non-Agression Pact signed between North Korea, South Korea, the US and other parties in the region?
That would at least be a start.