Thanks for the information on the qanat. I ran across one of these systems in Khost province. It was rather amazing as it ran better then ten kilometers from the river to and under a local town. The Afghans are so good at irrigation systems that they have learned how to make water run up hill. It is actually an illusion created by the step valleys but you would swear that it runs up hill.

Three other things. First, I think that the soil tends to fail from overuse and crops have to be rotated further limiting production.

Second, in places where that happens, and generally all around the country, orchards and in particular olives might be a better cash crop. I had heard while in county, but have been unable to verify, that prior to WWII Afghanistan had a flourishing olive oil business. I know these trees take years before they produce but they may be a better fit for the soil and conditions.

Finally, Pakistan and its constant battle with India still hampers the ability to export goods. Afghanistan is a few hundered miles from one of the largest and fastest growing economies in the world but could never hope to get its goods to market there.

Food for thought.