Nairobi, March 17 -- Africa's political parties may last long, but their members come and go, in search of power. But what happens when vibrant opposition movements crack under the weight of internal wrangles? Uganda, Burundi, Zimbabwe and most other countries in the region have seen opposition fights diluted by smart government operatives.

This week, Burundi's Agathon Rwasa, one of the biggest names in the country's opposition politics, found himself in the cold after his party, CNL, anointed new leaders.

But Rwasa read foul play from the ruling CNDD-FDD party. Burundian authorities rejected the allegations even though they deployed heavily at a function in Ngozi, north of Burundi, where the party's controversial congress happened.

Rw...