Nigeria, May 14 -- Yesterday, 13 May, Africa expected a moment of clarity.

At the Africa CEO Forum in Abidjan, five contenders vying for the presidency of the African Development Bank (AfDB) were slated to meet in public debate. It was to be a moment of visibility, transparency, and intellectual accountability - on African soil, before an African audience. With more than 2,800 public and private sector leaders in attendance, the symbolism couldn't be stronger. The stakes couldn't be higher.

But instead of a contest of vision, Africa got silence.

Three of the five candidates - Swazi Tshabalala of South Africa, Samuel Maimbo of Zambia, and Mahamat Abbas Tolli of Chad - declined to participate. Only Mauritania's Sidi Ould Tah and Senegal'...