There is an exhibit more ghastly and gruesome than the tatty stuffed Alsatian dog, awarded the Gustav Husak medal for sinking its teeth into a record number of attempted defectors from Communist Czechoslovakia, that graced a dusty museum in Prague. It is an axe in a glass case on the North Korean side of the demilitarised zone. In 1976, a group of American GIs attempted to fell a poplar tree in an area the North Koreans believed was off-limits to them, and the axe was turned against them by the ever vigilant border guards. Two US Army officers were killed in the incident.
The Alsatian, like the Czech Communist regime, is long gone, as is the the Iron Curtain border that once separated East from West. But in North Korea, the axe is still in its case, and the Cold War border between North and South is bristling and more dangerous than it has been since the end of the Korean War, in 1953. Ever since a team of international experts reported "overwhelming evidence" that a South Korean military vessel, the Cheonan, was torpedoed in March by the North Korean navy - resulting in the loss of nearly 50 sailors - the war of words has deteriorated into a tit for tat ratcheting up of the pressure on both sides. The world may have become accustomed to alarmist reports of brinkmanship on the Korean peninsula, but make no mistake, this is without doubt the most serious crisis since the armistice agreement was signed, not so far, incidentally, from the spot where the notorious axe is on display.
Almost a decade ago I was the first Western journalist to "interview" a senior North Korean military figure in his office on the DMZ. I say "interview" because General Ri Cham-bok let me leave my camera running on a table next to the teacups. His language then is the language of today. Back then, the South Koreans and their US allies were engaged in major military exercises. Back then - and this was before the temporary happier era of the "sunshine policy" of engagement between the North and South - the general spoke darkly of the "threat" facing his country. He said the Americans had tactical nuclear missiles, that South Korean planes were illegally entering the North's airspace. All of this was couched in the ever ready language of those who, as John Foster Dulles once remarked, thrive on the "existence or creation of the idea of a threat".
I have travelled widely in North Korea, or the Democratic People's Republic of Korea, as it prefers to be known, and have reported from that country on several occasions, though a recent interview I conducted with defectors from the North will probably prevent me from returning. I have seen North Korea's military in its full glory, met the country's head of state, Kim Yong-nam, stood 30 paces behind Kim Jong-il at the Ariyang mass games, and once even managed to get arrested for wielding a camera outside the Pyongyang railway station. None of this makes me an expert, but I think I have an understanding of the mindset of the ageing veterans of the Korean War who preside over the twin pinnacles of power - below the Eternal President Kim Il-sung and the Dear Leader Kim Jong-il - the Korean Workers' Party and the military.
North Korea's leaders have not escaped the shadow of the debilitating war, which saw more bombs dropped on the North than on Nazi Germany. Theirs is a world in which self-reliance is fused to Marxism-Leninism and Confucianism to the emperor system of old Korea. Limping along now on life support provided by China, the North is retreating into its comfort zone of isolation and outright hostility to what it sees as a hostile world. It does not help that Kim Jong-il is ailing, that the Korean Workers' Party and the military are jostling for influence, or that many of the younger technocrats whose political fortunes rose with warmer relations and improving trade and communications with the South have largely disappeared from view.
The North is denying, of course, that its torpedo sank the Cheonan, just as for years Kim Jong-il denied ordering the kidnapping of Japanese starlets who were forced to act in his movies. To the North Koreans, the rest of the world is not interested in its claim that the Cheonan was inside its waters. This possibly goes to the heart of what happened, since international experts have for some time argued that the "Northern Limit Zone" sea boundary between the North and South should be changed in the North's favour to take into account new rules that have extended maritime boundaries from three to 12 miles. That there has never been a final peace agreement between the protagonists of the Korean War does not help, either. It is possible that the sinking is a direct result of the jostling for influence between the military and the party, preparing for the post-Kim Jong-il era, but this seems fanciful, given the North's propensity to plan every move. What is clear is that the leadership of the North despises the South Korean government of the president, and now, with its abrogation of the non-aggression pact and the severing of all ties with the South, as well as a range of UN sanctions, feels it has nothing to lose.
Brinkmanship by the outside world should not be seen as a serious option, for such is the tension that an even a minor incident could lead to full-scale war. Which is why by far the most important figure to emerge in this crisis is China's vice foreign minister, Zhang Zhijun, a highly educated and cerebral man, who is urging caution and calm. Mr Zhang cut his teeth in China's diplomatic service, where I first met him in London 20 years ago. He is a scholar of European politics, open but cautious. He may not be able to act independently of his government, but having kept in touch with him - and having spent a fortnight with him visiting Outer Mongolian coal mines, southern China and Tibet some years back - I am convinced that he could play a vital role in helping to calm the tensions. It is not in China's interest for a conflagration to break out on the Korean Peninsula; nor does it want the North Korean state to implode. China does not want its effective boundary with the West to move up from the DMZ to the Yalu River.
It may be that we will hear rather more from vice minister Zhang in the coming days, especially if this crisis is deemed as serious as the last nuclear crisis involving the North. We know that Kim Jong-il recently visited China, and though Beijing is frequently irritated by the antics of its neighbour it will seek to calm the hotter heads on both sides. But I suspect that it will also have occurred to Mr Zhang and others in the Chinese leadership that while North Korea cannot be abandoned, still less be subsumed into the South, some Chinese-style economic modernisation, and even a less prickly and unpredictable post-Kim Jong-il regime, might just be worth encouraging.
So light-touch "regime change", conducted more with a whimper than a bang, and with China's involvement, has to be the best hope. Mark Seddon is the former UN correspondent for Al Jazeera English TV and a UK political commentator.