Are they dangerous? Yes. Do they commit terrorism? I wouldn't doubt it. Do they do stupid things sometimes? Sure. Are they insane? Almost certainly not and your examples do nothing to provide evidence to the contrary. Why even provide a justification for the shelling if they were insane? Do you really believe they do not try to act in their own self interest?
I haven't seen any evidence that the depiction that they-could-do-anything-next and are therefore immune to normal diplomacy and threats of force is anything but a caricature.
Again, I am not defending North Korea just pointing out distortions which impair making informed decisions and correctly interpreting world events.
That they commit terrible crimes isn't the question. This is:
When North Korean leaders make geo-political decisions do they act in their own self interest? As a state or even individuals?
The mad man caricature is an attempt to justify arbitrary action against North Korea, actions which would be much harder to justify against someone rational that could be influenced by carrots and sticks. It denies even the existence of motivations, however ill-intentioned those motivations may be.
I haven't seen any evidence that the depiction that they-could-do-anything-next and are therefore immune to normal diplomacy and threats of force is anything but a caricature.
Again, I am not defending North Korea just pointing out distortions which impair making informed decisions and correctly interpreting world events.