Re: Irrigate the Sahara

 In Roman times, North Africa was a fertile and very productive
wheat-growing region. After the Arab-muslim invasion, agriculture fell
into disuse and the topsoil was de d by the sheep and goats that
that the Arab nomads put out to pasture. Desertification followed soon
after. The French and Italian colonists had some limited success
irrigating small areas, but these efforts were abandoned shortly after
decolonization.-Jitney