Keeping up with the habit of commenting on events no longer current, I suppose the time has come to offer commentary on the semi-recent standoff in Korea.
In the 1950s People's Republic of Korea fought against a US-organised UN intervention that had more than a dozen active participants from Turkey to New Zealand to Luxembourg. Hostilities were brought to an end, not with the signing of a peace treaty, but of a mere cease fire. In the course of the war the United States mercilessly bombed North Korea and essentially erased all of its cities and towns, and killed up to two million Koreans. Since the war ended the US has maintained a comprehensive sanctions regime against North Korea obstructing its trade with the outside world. To this day the US keeps nearly 30,000 of its soldiers in South Korea, with which it has an agreement that in the case of the war restarting its military automatically passes under American control. Also permanently in the theatre is the US Navy's Seventh Fleet with 50 warships and 350 aircraft. In 2002 US named North Korea a part of the "Axis of Evil" along with Iraq and Iran and then proceeded to invade Iraq and to sponsor terrorism in Iran.
Despite all of this when the North Koreans on 23rd November bombarded South Korean military exercise taking place on a disputed island in South Korean hands, killing two soldiers and two civilians and wounding more, the news report all over the world adopted a tone bemused at another irrational belligerence of the nutty Northerners that simply can not lay off from trying to start a war. 'Fortunately' days later the Americans appeared on the scene — a US general visited the island to "inspect the damage" and the US Navy held joint military drills with the South Koreans in disputed waters — and reminded the world of the larger context.
Korean War was a traumatic event for the North Koreans. Since its ceasation the US has maintained a belligerent attitude towards North Korea, an impoverished country of twenty million in possession of a large, technologically outdated conventional army and a nuclear bomb that may, or may not, work. In response, the North Koreans, in order to maximise their deterrence capacity, are attempting to project the image of themselves as uncompromising, utterly unafraid and itching for a fight, all to make the Americans think twice about attacking them. Examined in this light the conduct of North Koreans in the frequent border incidents is anything but enigmatic, but is on the contrary perfectly rational. Also it does seem to be working to the desired effect; the US certainly shows North Korea a lot more respect than it did Iraq or Iran.
The truth is no aspect of the chilling North Korean state can be understood without reference to US presence in the region and its posture towards North Korea. Its ideological commitment to self-sufficiency is a predictable response to American attempts to isolate and blockade it. Its extreme militarism and regimentation is a consequence of the war never having been fully wrapped up, the heavy US military presence in the region and its hostile stance towards the North.
It is true the Korean War was traumatic for South Korea as well, but this is where the comparisons end. China, the main backer of North Korea, is not a menacing world hegemon currently engaged in at least three conflicts on foreign soil. It is a mostly peaceful country that has not been involved in a war since its incursion into (Communist) Vietnam 30 years ago. What is more China trades with South Korea to the tune of 140 billion dollars annually. Difference is, going about its business South Korea does not need to at every turn take into account the rabid hostility of a Great Power.