Every year when Robert Mugabe marks Independence Day with a visit to Heroes Acre – the monument outside Harare to the freedom fighters who gave their lives in the struggle against white rule – he places roses on the graves of his old rival Joshua Nkomo and, with a flourish of political theatre, his former wife.

Even by this old tyrant’s standards of duplicity it is a staggering piece of hypocrisy – one that Morgan Tsvangirai would do well to bear in mind. Those who choose to go to bed with the “old crocodile” do so at their own peril.

Mr Nkomo, a former opposition leader who thought he was acting in the best interests of his people, died a broken man, marginalised and humiliated by Mr Mugabe, a far more ruthless political strategist.

Unlike Mr Tsvangirai, Mr Mugabe has been here before. After months of negotiations, marked by point-blank refusals and violence between the two men’s followers, Mr Nkomo was given a seat in the Cabinet. In 1982 he was wrongly accused of plotting a coup and fled into exile.

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A furious Mr Mugabe declared: “Zapu [Zimbabwe African People’s Union] and its leader, Dr Joshua Nkomo, are like a cobra in a house. The only way to deal effectively with a snake is to strike and destroy its head.”

He then unleashed the North Korean-trained Fifth Brigade on Mr Nkomo’s Matabeleland homeland, killing more than 20,000 Ndebele civilians in an attempt to destroy Zapu and create a one-party state.

After the massacres Mr Nkomo consented to the absorption of Zapu into Zanu, resulting in a unified party called Zanu (PF). The rest is history. From then on Zimbabwe was in the iron grip of President Mugabe.

In a powerless post, and with his health failing, Mr Nkomo’s influence declined. When asked late in his life why he agreed to Mr Mugabe’s demands, he said he did it to stop the murder of the Ndebele who supported his party and of his political allies who were being targeted by Zimbabwe’s security forces.

In his autobiography, The Story of My Life, a disillusioned Mr Nkomo wrote: “Nothing had prepared me for persecution at the hands of a government led by black Africans.”

Many Zimbabweans look in dismay at Mr Tsvangirai and fear that history could repeat itself, hence the largely muted reaction by the population to the supposed landmark deal. Immediately after agreement was announced, Peter Hain, Britain’s former Africa Minister, sounded a note of caution, recalling how followers of Mr Nkomo were killed despite his reaching an agreement with Mr Mugabe, once an ally in the struggle that ended with Zimbabwean independence in 1980.

“Josh Nkomo went into a power-sharing deal with Mugabe to halt the suffering of his people. He took a secondary role in government and paid a huge price. The parallels with today are uncanny,” Heidi Holland, author of a recent book, Dinner with Mugabe, about the tyrant’s political rise to power, told The Times.

Ms Holland, a white Zimbabwean now resident in South Africa, added: “Mr Mugabe still praises the ‘unity pact’ with Nkomo. It was a disaster for everyone else but very successful for him . . . I am sure many people in the MDC (Movement for Democratic Change) are very nervous. Anyone can be duped by Mugabe, he is world class when it comes to political manoeuvring.”

Political analysts say that there is much concern within the MDC that its leader could be tricked by Mr Mugabe, 84. Some even say the deal could unravel before the signing ceremony, due on Monday.

“Not everyone is convinced about this . . . as ever the devil is in the detail but many a slip between cup and lip. Even after it is signed Tsvangirai will have to be on his guard,” said a political analyst close to the Opposition.

Mr Mugabe knows that the economy is in ruins. He also knows this deal could bring in a much-needed aid package. “If Tsvangirai delivers foreign support, he will have served his purpose. If the economy improves, Mugabe could ditch him. If it doesn’t he could blame him. He will have to be very careful,” Ms Holland said.

In Matabeleland today all that remains of the unity pact are a few pictures of the two men side by side. Mr Tsvanigirai can be forgiven if he looked a little uneasy in yesterday’s press photographs.

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