President Thabo Mbeki, whose slow but persistent efforts to negotiate a deal in Zimbabwe have brought him little but political brickbats, could be forgiven for feeling hard done by at today’s ceremony. At the moment of his greatest diplomatic triumph, a man often accused of being more interested in foreign than domestic affairs faces political ruin at home.

Last week’s decision by a High Court judge to dismiss 16 charges of corruption, fraud and racketeering against Jacob Zuma, his great political rival, has left Mr Mbeki in the line of fire. The judge agreed that Mr Zuma had been the target of a political conspiracy and accused the President of abuse of power. Mr Mbeki, already weakened when Mr Zuma ousted him from the leadership of the ruling African National Congress last December, now faces calls to step down before the end of his second term in April 2009.

A scholarly, complex man, given to citing Shakespeare, Mr Mbeki will be very much aware of Enoch Powell’s dictum that “all political careers end in failure”. He will feel he can blame his own demise on two very different Africans – the charismatic grassroots hero of the township poor, Mr Zuma, and the Marxist loner turned guerrilla leader, Robert Mugabe.

For years Mr Mugabe treated his neighbour’s interventions with contempt. He broke one commitment after another, leaving Mr Mbeki a laughing stock. Even Mr Zuma got in on the act. After he was elected ANC president he suggested he would take a much tougher stance on Zimbabwe. The promised policy change delighted Western countries, which reconsidered their initial unease at the prospect of a Zuma presidency.

Ironically Mr Mbeki could be the person to ensure today’s agreement finally delivers good governance for Zimbabwe. He has insisted the accord includes a monitoring group, made up of representatives from countries in the Southern Africa Development Community. Without Mr Mbeki’s presence, that monitoring group could become just another toothless diplomatic initiative that Mr Mugabe will ignore.

It would be ironic if Mr Mbeki now has to listen to Western states lamenting his absence from the diplomatic playing field.

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