Here’s a not very hard trick question. What is it that Iraq and Libya didn’t have, that Iran might (or might not) be interested in acquiring, and that North Korea appears to definitely have?
The answer, of course, is the capacity to build an nuclear warhead. Iraq and Libya had both agreed to give up their nuclear programmes a few years before each was attacked and their leaders put to death. Iran is being threatened with all kinds of consequences if it doesn’t stop a programme it doesn’t actually seem to have.
Which leaves North Korea. Although it’s a much easer target than Iran, with conventional forces that are basically useless, you won’t find western politicians hyperventilating about
attacking liberating Pyongyang. Why? Because North Korea has the ability to deter the West from an attack with its hundreds (possibly thousands) of short and medium-range conventional missiles targeted at Korean and Japanese cities. Pyongyang judges (correctly) that no likely American government would sacrifice potentially millions of dead and wounded for the pleasure of bringing North Korea down. But supposing a religious maniac takes over the White House (not an impossibility, most would say) and launches an attack because God told him to? You need some way of defeating the US, or at least inflicting unacceptable casualties on that nation. A small handful of nuclear weapons would do that, especially as hardly any military equipment these days is hardened against Electromagnetic Pulse. North Korea does not want a capability to attack the United States – that would be pointless, even if it were technically feasible. But a few nuclear warheads, with no need for a sophisticated delivery or guidance system, or even a large yield, would ensure the regime stays in existence, which is what it wants above all. It’s taken a major step in that direction.
To adapt the old joke: what do you call the dictatorial leader of a small, impoverished nation with nuclear weapons?