IS NORTH KOREA telling the truth when it says that it now has nuclear bombs? What did the regime hope to gain by boasting of its armoury this month? And why did it simultaneously walk away from the negotiating table, not only the six-power version it was always reluctant to accept, but the bilateral talks with America it had been demanding? Disarmament experts generally insist that what matters is capability, not statements of intentions, and they are generally correct. Yet in the North Korean case, what lies behind this latest manifestation of shock-horror diplomacy may be more immediately relevant than a weapons inventory.

The point is this. Bad behaviour is expected of North Korea, and its determination to become a nuclear power has been factored into international policy for most of the past decade. Militarily, this announcement does not change much; the more critical question is whether it can yet deliver nuclear weapons, either by bomber or missile. On the political plane, Pyongyang’s “attack diplomacy” — the phrase comes from its own domestic propaganda — has lost some of its power to shock. Having been caught cheating, the regime’s pickings from nuclear blackmail are not as rich as they were. Pyongyang has pretty much been left to swing since it refused last summer to rejoin the six-power talks.

If this was a bid to get the bribes flowing again by reinforcing North Korea’s reputation as a dangerous and potent potential belligerent, it could backfire. Boasting about its bombs thoroughly annoys Beijing, which has been counselling patience on the questionable basis that a nuclear-armed North Korea was some way off. In Japan, already livid about North Korean lies about the fate of the Japanese citizens it abducted, this move can only intensify the public demands for sanctions.

The US is looking hard at ways to squeeze the regime financially, notably by choking off North Korea’s lucrative trade in drugs and counterfeit dollars — it is reputed to make the best $100-bill forgeries in the world.

Bankrupt North Korea is vulnerable; even a 10 per cent cut in Chinese oil supplies would hit it hard. In Chairman Mao’s words, Kim Jong II would appear to have lifted up a stone to drop it on his own platform-soled foot. What made him do it? One obvious explanation is that the next round of six-party talks was to be put-up-or-shut-up time: Pyongyang was due to respond to specific US proposals for dismantling its nuclear programme. The other possibility is that potentially explosive splits within the North Korean leadership lie behind its apparent decision to abandon negotiations that might expose internal disagreements to external scrutiny.

That would really set alarm bells ringing. South Korea is not alone in conniving, grim-faced, at propping up a foul and bankrupt totalitarian regime out of fear that it could be still more dangerous if it began to disintegrate. Our ignorance of what goes on inside Pyongyang’s tiny elite is greater, even, than the uncertainties surrounding its efforts to acquire nuclear weapons. The thing the land of the Dear Leader does best — indeed, the only thing other than running torture cells and slave labour camps it does at all well — is hiding from outsiders who decides what, and how. As Donald Gregg, a former CIA station chief and then US Ambassador in Seoul, once observed, the place is the world’s “longest-running intelligence failure”.

In this obsessively secretive tyranny, scraps are all that outsiders have to go on. But they increasingly point to power struggles at the top, spreading disgust with corruption, rising drug abuse and breakdowns in social order.

Kim himself has not been seen since September. He has gone to ground before, and this could be depression following the death of his favourite consort Ko Yung Hee, “esteemed mother” of two of his sons. But Chang Song Taek, Kim’s powerful brother-in-law, has been purged and is rumoured to be under house arrest, reportedly for trying to oust these sons from the succession in favour of his own son-in-law. Last autumn, Austrian police foiled an assassination attempt against Kim ’s eldest son, Kim Jong Nam.

In a country so given over to Kim-worship that the merest hint of a lack of enthusiasm for the Dear Leader can send three generations of a family to perish in labour camps, his portrait has been taken down in some public buildings. Why is not known; but what is known is that despite their terror of the secret police, Koreans who starved silently in the 1990s are starting to blame Kim for those famine years. Dissent is still scattered, but graffiti and wall posters have appeared and last month a shaky video reached South Korea showing a portrait of Kim, in the town of Hoeryong, defaced with the slogan: “Down with Kim Jong II! People, let’s all rise up and drive out the dictatorship!”

Discontent is fuelled by corruption and hyperinflation, the most tangible consequences of the botched “monetisation” of the economy in 2002. Factory managers, ordered to be self-supporting and unable to pay wage bills, stripped out machines and flogged them across the Chinese border. Farmers’ markets now openly trade in smuggled goods; but most Koreans can barely manage to eat. Travellers in North Korea describe child beggars, controlled by teenage gangs, haunting the streets even in Rajin, the “showcase” free port in the northeast. North Koreans are daring in rising numbers to escape across the border. There may now be 300,000 North Koreans living, fearfully and illegally, in China.

The power most able to act against Kim is the Korean People’s Army. Chinese academics report an increase in high-level defections. Still more intriguingly, dissidents report that China has engineered the “secondment” of senior KPA cadres, to courses from which they have not returned. Chinese exasperation over the nuclear standoff is increasingly undisguised; a military coup that kept Pyongyang still in the socialist camp, but more tractable and predictable, would suit Beijing nicely. These old allies are, famously, “as close as lips and teeth”. Could China, to prevent a nuclearised Korea, be preparing to bare its teeth?

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