As I said, there was a decline in 20th century. That happens sometimes. Regardless, the notion that they "are just now beginning to irrigate" is demonstrably false.
When it didn't rain, they starved.
Even Recently, Cape Town is on the edge of running out of water.
Ahh, self rule! (is the proof of the pudding)
I didn't decline to respond to the rest of your post as a "cop-out", I'm just tired of addressing the same stuff over and over again on here. It's a waste of time.
And if you're not willing to address it/answer, stop posting/last-wording.
Again: I presented the undebatable big picture showing the Incredible Backwardness of sub-Sahara relative to Europe and Asia,
sub-Saharans were still 98% Hunter-gatherers thousands of Years after Rome and the Chinese Civil Servce system.
They lived in 1900 app the same a they did 60,000 years ago.
Many still live that way!
Hunter gatherers in huts.
There can be no answer. It's a Fact.
So you disingenuously tried dismissal... twice
You got Busted.. twice.
Note below, another 100% last-wording whiff by Ighayere.
No answer to the above and it's previous two iterations.
There is none.