What would we do without North Korea? Yes, the place can be scary – like right now. But in our world of instant experts and instant explanations, what a delight to discover something genuinely mystifying, an issue on which the most self-confident pundits are stumped for answers.
So to the latest chapter of the riddle. Why on earth did the North sink a South Korean warship in March, killing 46 sailors and setting up the sharpest confrontation on the Korean peninsula since 1994, when the US came close to a pre-emptive attack on North Korea's nuclear reprocessing facility, and Pyongyang threatened to turn Seoul into a "sea of fire"?
An international report last week banished the doubts of all but the most indefatigable conspiracy theorists that a North Korean torpedo was responsible. But even at less fraught moments, the country has a way of thrusting itself into our consciousness, whether we like it or not. On anyone's list of places where the next major hot war could start, the Koreas are right up there with Pakistan, the Gulf and the Middle East. Had Washington gone ahead with its attack on the reactor at Yongbyon, the Pentagon estimated that the consequence would have been a war that killed at least one million people.
Today, the rhetoric of the two sides is incandescent, and the "sunshine policy" of reconciliation to which the South doggedly clung for more than a decade is history. As it severed trade links this week among other reprisals, Seoul described the North as its "arch enemy". Pyongyang retaliated by cutting all its ties with the South, while President Kim Jong-il reportedly put his armed forces on combat alert, sending South Korea's stock exchange tumbling.
Yesterday, the North ratcheted up the tension another notch by announcing it was scrapping an agreement designed to prevent accidental naval clashes, at the very moment South Korean warships were starting exercises close to long-disputed territorial waters.
One misstep in this choreography of threat could lead to calamity. North Korea has the world's fourth-largest standing army, at least half of it dug into position within 50 miles of the border. North Korean heavy artillery could unleash a barrage that would devastate Seoul, home to 10 million people and just 35 miles south of the Demilitarized Zone that divides the two countries. In other words, the North could launch a surprise land attack at any moment, without giveaway troop movements beforehand. Almost certainly, they would make deep inroads into the South, where they would run into some of the 28,000 US troops stationed in South Korea as an explicit guarantee that the US would enter any such conflict.
This isn't idle war-gaming. Exactly 60 years ago next month, the North did invade, overrunning Seoul and starting the Korean War, in which at least two million died. The difference now, of course, is that North Korea is a nuclear state. Since 2006, it has carried out two nuclear tests, and may possess up to eight warheads. And just for good measure, after the second test, in May 2009, Pyongyang announced it no longer considered itself bound by the armistice that concluded the 1950-53 conflict.
In fact, the reality is slightly less chilling. The North might win the early battles, but not the war. South Korea and the US enjoy a vast air superiority, and the North's chronically weak economy surely could not sustain a massive war effort for long. Which only makes Mr Kim's latest provocation harder to fathom.
Naturally, there is no lack of theories. One is that the sinking of the Cheonan was in revenge for a naval skirmish last November, which the North Koreans lost. Another is that Mr Kim's belligerence is for domestic consumption, part of an opaque power struggle in which a sickly dictator is trying to bolster the credentials of his untried 27-year-old third son, Kim Jong-un, about whom the Great Leader's generals are said to have grave doubts.
Yet another is that the escalation of tension is somehow related to the long-stalled negotiations to get rid of North Korea's nuclear weapons. Or maybe it could be that the North simply wants to remind people that it's still there, that it still matters.
Whatever the truth, such incidents have happened before – most recently in 1987, when North Korean agents, reportedly acting on the personal orders of Mr Kim, planted a bomb that exploded on a South Korean airliner in midflight, killing 115 people. And so, once again, we have the extraordinary spectacle of a baffled world held to ransom by the antics of a small, poor and distant country, led by an odd-looking little man with a penchant for Scotch whisky, cognac and Western movies, and travelling in armoured trains – and whom some contend may already be dead.
What seems certain is that Mr Kim suffered a stroke two years ago, raising the question of his succession. Those doubts were briefly laid to rest when Bill Clinton was photographed with Mr Kim when the former president travelled to Pyongyang last summer to secure the release of two US journalists who had strayed across the border from China.
The North Korean leader seemed in remarkably good shape. But was it really him? Mr Kim is not the first dictator believed to have used lookalikes (Saddam Hussein was another), but the Japanese professor Toshimitsu Shigemura maintains that Mr Kim died of diabetes in 2003, and a doppelgänger has replaced him since, at his rare meetings with foreign leaders.
But, you may ask, why cannot the West rid itself of this irritant? After all, an alliance featuring the world's only superpower and the economic powerhouses of Japan and South Korea ought to be able to bring pipsqueak North Korea to heel. One reason for what Washington terms its "strategic patience" is those nuclear weapons. The other is China, North Korea's patron and economic lifeline. Chinese intervention saved the North from defeat in the 1950-53 war, and China is responsible for the stalemate now.
Consider the options from Beijing's viewpoint, and its stance makes perfect sense. North Korea's regime might or might not face terminal collapse without Chinese aid. But if it did collapse, two things would probably happen. There would be a destabilising influx of North Korean refugees into China, followed by the absorption of the North into the vastly richer and more populous South – just as West Germany swallowed an imploding East Germany two decades ago.
That would mean a single pro-American state on China's north-eastern border. If so, score a huge victory for Washington on the East Asian geopolitical chessboard, and an equal setback for Beijing. There is, of course, a third option, of moving in concert with the West against North Korea – but that would surely see Mr Kim turning his spite against Beijing as well. One way or another, China wants to preserve the status quo, and its economic leverage over the US gives it means to do so. Unsurprisingly, therefore, Beijing has conspicuously failed to endorse the findings of the international commission on the fate of the Cheonan.
But even China's hesitations do not entirely explain how Mr Kim continues to get away with it. Some see the answer in his personality. Psychologists have claimed that Mr Kim shares with Saddam (and to a lesser extent Hitler) several typical traits of the tyrant: among them sadism, paranoia, narcissism, and an antisocial and schizoid mentality. You might add another: an instinctive gift for blackmail. After the Cuban missile crisis, few seriously believed Russia or the US would pull the nuclear trigger and ensure their own obliteration. But with the man in Pyongyang, and his carefully cultivated reputation for unpredictability and perverseness, who knows?
That consideration – along with the fact that the country is so isolated already that UN sanctions have next to no effect – might explain why Mr Kim can take steps that ordinarily would hurt his own country more than his adversaries. But it doesn't resolve the question of why the country puts up with it. Maybe fiction, rather than pundits, has the answer.
A few years ago, James Church, the nom de plume of a former US intelligence officer who in his own words spent much of his career "in, around or over North Korea", wrote A Corpse in the Koryo (the Koryo being the main hotel for foreigners in Pyongyang). It's not just a detective story, but a window into an alien world. Church's hero, the solitary and world-weary Inspector O – a sort of North Korean Inspector Morse – muses on the seeming xenophobia of his deprived and downtrodden country.
"It's not foreigners, it's ourselves we don't like," O tells a foreign intelligence agent. "In our minds, we are small, quivering, bowing, submissive, beaten, cowering dogs. If we like foreigners, it can only be because we are afraid, or currying favour, or kissing their feet."
Might not the fictional inspector be hinting here at a deeper truth? Might not the belligerence and provocations of the world's last Stalinist state be a version of the bargain that helped keep the Soviet Union in being for so long, whereby people put up with misery at home, in return for being feared abroad? Mikhail Gorbachev's mistake was to renege on that deal, by removing the fear factor abroad, yet failing to provide prosperity at home. Could Mr Kim be calculating that if he started making nice, his regime would go the same way as Gorbachev's?
Neither we nor the inspector really knows. "Where I live, we don't solve cases," he says, "for what is a solution in a reality that never resolves itself into anything definable?" Right now, the West's leaders, war-gamers and real-life pundits would heartily agree.