Why is Africa so screwed up?

I have been asked this question before by commenters pushing hard-line racial theories of IQ. From which it's clear that they really do believe in an innate theory of intelligence, because there is, after all, an extensive literature on the subject with which none of them seems to be familiar.

Yes, Asia had a colonial regime, and Africa had a colonial regime, but that doesn't make them the same continent. Asian colonization was nowhere near as extensive as African colonization, and my understanding is that it tended to rely much more on co-opting existing power structures than building entirely new ones. That's because Asia had existing power structures to co-opt--local imperial barons that controlled large amounts of land. Moreover, much of Asia was not, in fact, colonized: the biggest Asian success stories right now (China, Japan, Korea) had repeated incursions by Western interlopers, but were never colonized in the formal sense that Africa was. It's worth noting that the bits of Asia that were colonized tend to be in worse shapes than the bits that werent.

At any rate, there's a whole, very large literature on why Africa is particularly screwed up. The awful climate under which most of it labors. The bad maritime geography: apparently one of the two coasts offers extremely little scope for building ports, the rivers don't go where you want them, and when they do happen to meander near something interesting, they are hard to navigate. The huge patchwork of ethnicities. The bad borders--in Asia, borders were drawn somewhat along ethnic power lines, whereas in Africa, they were drawn mostly to suit the convenience of whatever western country wanted to do business there after the colonian powers left, and there is an emerging literature indicating that border that cut across ethnic lines are a recipe for conflict, and thus poverty. The unique medical problems of Africa--what with us having emerged there, the local bugs have had longer to develop a taste for us than elsewhere, and there are lots of reservoirs of new disease in our near genetic cousins. And that's just scratching the surface. Africa has a lot of unique factors that we've identified causing huge problems in other places, all squished together into a toxic cocktail.

It's not that it's impossible that IQ varies by race--but we've got a lot of other variables that can account for our problem, so why look to race first, last, and only?

Update Yup, those were typos; one Asia changed to Africa, and one India to Korea. Next time, coffee before blogging, not the other way around . . .