Every country that doesn't have a democratic government with strong protections of individual rights should fear America.
EDIT: Either way, North Korea is most likely developing nuclear capabilities as a defensive measure. If they ever succeeding in producing an ICBN, it is unlikely that they would proceed to attack another nation. It is far more likely that the mere threat of such capabilities is useful toward the ruling party as a means of ensuring they remain in power and safe from foreign intervention.
I trust nobody has forgotten about MAD.
I'm sure they don't want what happened in Libya to happen to them, and they probably aren't trusting China to back them in the future.
P.S. I have no clue about the current event... I'm just making assumptions based on Yosuf's post.