One of the twists, when you're considering African nations, is that most of them had their borders drawn by empires, and almost all of them (maybe all) encompass more than one and often many peoples as different from each other in culture and language as the Spanish are from the Finns. Congo, for example, is as large as western Europe, includes many ethnicities at odds with each other, and given it has been the site of Africa's world war since shortly after the Rwandan genocide in the 90s, you could say that it, too, has failed as a nation-state.