Not to mention that Africa holds three countries named Guinea, but none of them are very like each other. It's just something with a history that can't be divided into the usual imperial framework as European and Asian history. The fact that there is such a large difference between urban and rural in some places in Africa also warps perceptions. It makes us think of Africa as a single thing, not a complex tapestry.

Botswana is the favorite for the development enthusiasts, who tout it as one of the continent's success stories (our mixed history with Nyerere taints our memory of Tanzania I think). But until people can go fairly easily to all of Africa they're unlikely to think of it as anything but a distant, exotic, and broadly characterizable place.