Kim Jong Il is a narcisist who desires displays that give him a perception of legitimacy. And as with most narcisist when he does not get the reinforcement of his self delusions that he desires he throws a tantrum to get attention.

Being the absolute leader of an indestrialized nation makes it so that he is able to throw some pretty impressive tantrums. The way you deal with people like Kim Jong Il is to isolate them politically and economicly, while at the same time petting their ego. This keeps the "child-leader" placated and peaceful while at the same time reducing the leader's ability harm those outside the leader's country.

Bush made a big mistake by choosing to ignore Powell's suggestions on how to deal with North Korea. Because by ignoring North Korea and publicly insulting Kim Jong Il it only serverd to fuel Kim Jong Il's narcisistic need for attention.