Michael Walker in the Eurasia Review:
What the North Korean leadership is hoping to achieve by its belligerence is anyone’s guess. As a “senior U.S. official” told the Reuters news agency that, when it comes to Kim’s strategy, “It’s a little bit of an ‘all bets are off’ kind of moment.” Several possible explanations suggest themselves, though. First, it may be that Kim is simply attempting to secure his power base by standing up to the “imperialists” in Washington. It would be understandable if he felt the need to bolster his position domestically, for he is a mere 30 years old and faces the monumental task of solving the country’s “chronic economic problems,” while at the same time keeping the 1.2 million-strong army on his side.
A second possibility is that he is employing former U.S. President Richard Nixon’s “Madman Theory”: Give the other side the impression you are capable of doing anything, including using nuclear weapons, in the hope of winning concessions at the negotiating table. Again, considering the DPRK’s perilous economic circumstances, this strategy would make some sense.
A third, and less probable, explanation is that Kim really wants to provoke a military clash with the United States and its allies. Given the isolated nature of his regime, there is at least a chance that he believes the DPRK has the means to emerge victorious in such a confrontation.
Another unknown quantity in this supercharged state of affairs is Park Geun-hye, South Korea’s first ever female president. Her month-old administration is already reeling from a series of scandals, leaving her weak at a time of potential national crisis. She would be under enormous pressure to reply with force were the North to launch even a limited military strike. Her predecessor was castigated for his vacillating response to North Korea’s alleged sinking of a South Korean ship and bombardment of a disputed island in 2010, which led to the resignation of the country’s defense minister.