The Real North Korea: Life and Politics in the Failed Stalinist Utopia. By Andrei Lankov. Oxford University Press USA; 283 pages; $27.95 and £16.99. Buy from Amazon.com, Amazon.co.uk

WESTERN politicians like to grandstand about North Korea, calling its leaders “mad”, “rogue” or “tinpot” (The Economist has been known to do this too.) In fact, North Korea is the world’s most rational despotic regime: a highly successful Communist absolute monarchy. Kim Jong Il, son of the country’s Stalinist founder, Kim Il Sung, failed as a leader by any of the usual standards—he enforced North Korea’s isolation and presided over a famine that killed between 400,000 and 2m people. But he succeeded in what counts. He lived a long time, died peacefully in late 2011 and passed power on to his son. In the same way that betting once raged about how briefly Kim Jong Il would last after his father’s death in 1994, so too are outsiders now calling time on North Korea’s fun-loving heir, Kim Jong Un (pictured). It may be a triumph of hope over experience.

Andrei Lankov is an arch-realist. The author of an incisive new book, “The Real North Korea”, he grew up in Soviet Russia, studied for a while at Kim Il Sung University in Pyongyang and now teaches at Kookmin University in Seoul. He is rare in having an unsentimental feel for the regime’s psychology of survival and for the mindset of those outsiders who would like to change North Korea but who, in the process, often succumb to wishful thinking.

For all its self-imposed isolation, North Korea since its inception as a Soviet creation in 1948 has depended for survival on a small, shifting, group of nations, which it has shaken down with consummate skill. Most aid these days is hoarded by the elites. But, as Mr Lankov explains, the regime did not set out to oppress its people. Kim Il Sung’s early promises included giving North Koreans a daily meal of meat soup and boiled rice, eaten under a tiled rather than a thatched roof. That appealed to a poor, agrarian people. Even today, after so much disillusionment, the ceaseless propaganda depicting the Kim dynasty as parents-in-chief, protecting a vulnerable nation from American and Japanese wolves, works to a remarkable degree.

Loyalty, however, was also won through ruthless purges of potential enemies, and through the North’s unique and horrifying songbun, a caste system in which families are classified as friendly, wavering or hostile, according to their historical, political and economic background. The efficacy of songbun as a tool of state control lies in it being forward-looking as well as regressive. Until recently, at least, not only did those suspected of disloyalty face official discrimination; so did their children and grandchildren. Whole families were thrown in the gulag.

As for outside pressure, policy towards North Korea has oscillated between soft and hard. Both approaches are doomed, Mr Lankov argues. The soft line—treat the North gently, reward it with concessions, and it will give up its nukes—flies in the face of repeated provocations, including yet another nuclear test in February. It requires outsiders to turn a blind eye to grotesque abuses of human rights. And it assumes that the regime can be persuaded to undertake Chinese-style economic reforms. But it cannot do this without collapsing, since the North is in ideological competition with South Korea, whose economic model, the regime knows, wins hands down.

The hardline version is no better. Any threat of military retaliation against the North is simply not credible. Greater Seoul, with 24m people, is within range of 250-300 pieces of North Korean artillery. Neither South Korea nor the United States will ever start a war unless seriously provoked, and there is little risk of that. The North’s strategy of manufacturing crises in order to wring out concessions will certainly continue. America has taken up a posture of “strategic patience”. But it cannot ignore the North Korean regime nor leave it alone; the Kim family will not let it.

The Kims are playing a long game, but one day their dynasty will collapse, brought low by the widening income gap with South Korea which will be impossible to conceal. Perhaps the most interesting, if hardly the most cheering, part of Mr Lankov’s lucid book lies in “being ready for what we wish for”. The post-Kim era risks being a dramatic and brutal upheaval. It will take decades to clean up after the Kims’ long misrule.

Even the promise of reunification with the South will bring disillusion. Poor North Koreans will be exploited by South Korean employers and tricked by financial scammers. Members of the former regime, their criminal skills already honed, will seize chunks of the economy and even prey on hitherto safe South Korean cities. And what fate awaits educated North Koreans? Doctors can make drips out of beer bottles, but know nothing of the modern pharmacopoeia. The typical history teacher, Mr Lankov says, “knows a lot about events that never actually happened”.

One intelligent move would be to re-examine how the West undermined the Soviet Union and the Communist bloc, and start doing the same. Sponsoring radio stations that broadcast into North Korea and offering scholarships for refugees would be a good start. Both these would cost relatively little and would help North Koreans when they face the coming calamity. Unfortunately, for the moment Western politicians prefer grandstanding.