Gets tricky when the immortal die

The general secretary has a cold. The president is feeling much better. Our leader is suddenly indisposed and on his way to hospital.

Such were the official explanations when, respectively, Leonid Brezhnev, of the Soviet Union, had three days to live due to a multitude of illnesses; Laurent Kabila, of the Democratic Republic of Congo, was shot dead by a bodyguard; and Bingu wa Mutharika, the deranged leader of Malawi, was struck down by a heart attack.

Now the "Supreme Leader" of North Korea, Kim Jong-un - who inherited the throne of his "Democratic People's Republic" in 2011 - has suddenly vanished from sight.

All we have to go on are the cryptic words of state television: Kim is said to have an "uncomfortable physical condition". It is a trifle odd for a 31-year-old to be so afflicted. Already wicked rumours are spreading to the effect that the "Brilliant General" has been done away with and replaced, probably by a real general.

Until now Kim had achieved only one distinction. Last year, he became the first leader in history to have himself photographed supposedly in the act of ordering "merciless" nuclear strikes on the US. Today he has become the youngest dictator ever to succumb to an "uncomfortable physical condition".

All dictatorships have a compulsion to treat a leader's health as taboo and his death as an official secret, to be covered up for as long as humanly possible.

In countries with no law and no institutions, everything depends on the man at the top. The whole edifice of government - and the flow of favours and patronage that it dispenses - rests on the immortality of the supreme leader. When the great helmsman proves to be mortal after all, it invariably threatens what Saddam Hussein might have called the "mother of all crises".

The minions whose fortunes, careers and possibly lives turn on the survival of the dictator, need a breathing space in which to prepare to deal with the tumult that will be unleashed by his death. Hence the urge to buy time by pretending that nothing has happened.

After Kabila was assassinated his entourage bundled his corpse on board the presidential jet and flew it to Zimbabwe, a country ruled by his only real ally, Robert Mugabe. There, Congo's ambassador to Harare, Kikaya bin Karubi, was ordered to maintain that, although Kabila might indeed have got into some unfortunate scrape with a disloyal bodyguard, there was nothing seriously wrong with him.

When I rang Karubi, he duly told me: "I have just been to see the president and he is feeling much better." Put it down to a journalist's cynicism if you will, but I knew then that it was over and out for Kabila.

Why was I so sure? Just over a year earlier, I had tried to discover the fate of Joshua Nkomo, the corpulent veteran of Zimbabwe's struggle against white rule, who then served as Mugabe's vice-president. For weeks, Nkomo, 82, had lain stricken in a Harare hospital. When I rang to inquire after his health, I was put through to his ward where a cheerful nurse said the fateful words: "Comrade vice-president is feeling much better."

No one was less surprised than me when Nkomo's death was announced the following day.

Omar Bongo, the kleptocrat extraordinaire who ruled Gabon for 41 years, flew to Spain in 2009 for urgent medical treatment.

On June 8, Gabon's prime minister smoothly assured the world that Bongo was "alive and well". By then, Bongo had been dead for at least a day. But the duplicity bought time for the succession of none other than the president's son, ali-ben Bongo, who rules Gabon today.

So ask not for whom the bell tolls - it assuredly tolls for the "beloved of his people" dictator who is "alive and well".