Opinions vary widely among North Korea watchers . Theories include a show of strength and a miscalculated reaction to an apparent threat . Comment: Yet another theory : Pyongyang needs constant military tension to unite its people .
Opinions vary widely among North Korea watchers . Theories include a show of strength and a miscalculated reaction to an apparent threat . Another expert says the North is frustrated by being ignored diplomatically . Yet another theory : Pyongyang needs constant military tension to unite its people .