To the uninitiated, President Mugabe’s declaration today that he had stopped the cholera epidemic in Zimbabwe may seem like the remarks of a deluded old tyrant living out his last day’s in a parallel world.

As hundreds of his countrymen succumb to the deadly disease and thousands more are infected - with no government effort to stop the outbreak - he has simply declared the crisis over.

In a country where he controls all the media, persecutes the opposition and bans foreign journalists, who is to challenge his absurd pronouncements?

But it would be a mistake to imagine that Mr Mugabe is unhinged or unaware of what is happening in Zimbabwe. His remarks are based on a perceptive assessment of the situation and reveal that he is more concerned than he lets on.

Ever since Mr Mugabe decided to use violence and intimidation as a means to stay in power, he has been very careful to apply force expertly. While the lives of his fellow Zimbabweans have been ruined - and millions have fled abroad - he has until now largely contained the problem within the country’s borders.

This has made it far more difficult for his opponents in London and Washington to press for international intervention, which is usually justified because a country poses a threat to the security of an entire region.

Certainly the regional superpower South Africa has shown no appetite for intervening in Zimbabwe. Moscow and Beijing, who can and have vetoed resolutions on Zimbabwe, have similarly insisted that it is not the business of the outside world to interfere in Zimbabwe’s internal affairs.

The cholera epidemic changes all that. The disease has now spread into South Africa and threatens other neighbours.

Unfortunately for Mr Mugabe, the easy ride he has enjoyed for the past decade of violence, corruption and mismanagement could soon be over. A new leadership in South Africa under Jacob Zuma, the head of the ruling African National Congress, is unlikely to be as a patient as Thabo Mbeki. Privately Mr Zuma has let it be known that he cannot stand Mr Mugabe.

There will soon be a new president in the White House. Unlike his predecessors he is half African and, as The Times recently revealed, his own grand-father took part in the liberation movement against British rule in Kenya. Barack Obama will be much more difficult to dismiss as an agent of Western imperialism.

Put this together and Mr Mugabe may fear that his enemies will use the cholera epidemic to justify a humanitarian intervention in his country, possibly backed by troops covered by UN mandate (as they were in Bosnia).

Mr Mugabe put his finger on the problem today when he said: “Now there is no cholera there is no case for war.”

We know his first premise is ridiculous. He must know that his conclusion is also wrong.

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