Contrast all of that with the SADC's pussyfooting around Zimbabwe's Mugabe

He must have read with envy at the weekend the news that the Economic Community of West African States had imposed an arms embargo on the military junta-ruled Guinea for "mass human rights violation".

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Even as he headed for South Africa for the first in a series of meetings he hopes to hold with regional leaders, Tsvangirai would have known that there was no hope of the Southern African Development Community adopting a stance against Zimbabwean President Robert Mugabe as tough as the one taken by Ecowas on Saturday against the leaders of Guinea and Niger.

In case you have missed your continental news, here is an update: Following the massacre of, reportedly, more than 150 people at an opposition rally in Guinea last month, Ecowas convened an emergency summit in Abuja on Friday.

But unlike those "crisis summits" we have become accustomed to in the southern part of Africa, the Ecowas meeting was no talking-shop.

West African leaders, headed by Nigeria's Umaru Yar'adua, reacted by slapping Captain Moussa Dadis Camara's regime with an arms embargo.

They also mandated Yar'Adua to lobby the African Union, the European Union and other international bodies to do the same.

In a statement issued after the summit, Ecowas described the state-sponsored violence in Guinea as a "real threat to the peace, security and stability" of the entire West African region.

"All steps must be taken immediately to stop the spate of killings of innocent Guineans who are yearning for immediate restoration to constitutional order," Yar'Adua later said.

The summit also threatened to impose "full sanctions" on Niger if President Mamadou Tandja went ahead with his unconstitutional plans to serve a third term as head of state.

Now contrast all of that with the SADC's pussyfooting around Mugabe, who continues to give regional leaders the middle finger. For that is what he has done by plunging the SADC-sponsored, and shaky, Zimbabwean government of national unity into a fresh crisis.

If he were serious about making the unity government work, Mugabe would have stopped his foot soldiers from harassing Tsvangirai's close ally and the MDC's deputy minister-designate, Roy Bennett.

Bennett's most recent detention was calculated to provoke Tsvangirai and the MDC into pulling out of the unity government. But the collapse of the unity government would not only be a blow to those within Zimbabwe seeking peace and stability, it would leave the SADC - especially South Africa - with much egg on its face.

For years, the region has successfully persuaded the rest of the world that it should not intervene in the Zimbabwean crisis because the SADC leaders were the best placed to resolve the conflict.

Then, a year ago, it seemed that the SADC - and especially former president Thabo Mbeki - would be vindicated, as Tsvangirai and Mugabe concluded a historic power-sharing deal.

But it has been downhill ever since, with the Zanu-PF leader reneging on key components of the agreement.

Despite calls for help from a desperate MDC, the SADC has done very little to ensure that Mugabe meets his end of the bargain.

Would Ecowas have allowed such total disregard of its authority by a member state? I think not.

Academic Adekeye Adebajo once said that bodies such as Ecowas and the SADC need "local hegemons like Nigeria and South Africa" to provide leadership. Nigeria is now doing just this for West Africa, while we in the south are left asking: Where is South Africa?