There are tensions in three African countries that share a few features. In Guinea, about 120 protesters demanding regime change were killed recently. This was followed with imposition of martial law.

In Zimbabwe, the economy has collapsed; inflation has hit 1,600%, the highest in the world, and average Zimbabweans are severely hit by unemployment and food and fuel shortages.

In Senegal, there are clashes ahead of Sunday’s general elections.

For all the three countries, their leaders are old and two have been in power for decades. Robert Mugabe of Zimbabwe is 83, Abdoulaye Wade of Senegal 81 and Lansana Conte of Guinea is 72. Mugabe has been in power for 27 years, Conte for 23 years and Wade has been in politics since the 1970s.

Yet, no one is sure when these leaders may retire. ZANU-PF wants to push presidential elections by two years to 2010, and Mugabe won’t say whether he will stand or not – at least for now. Wade has been campaigning on promises of a brighter future and Guinea’s unrest was sparked off by Conte’s refusal to relinquish power.

Staying in power for long is not bad per se, especially if one is still young, in good health and energetic. But Conte is ailing, Wade is frail and Mugabe is an octogenarian. This is why Mandela stands above the crowd, for after 27 years in prison – longer than some leaders have been in power – he retired before he was 80.

Above 70 years, one is likely to have great grand children. Septuagenarians could be advisers and references for their successors but they should leave active politics to the younger generation.