In fact, since the 1970s, the almost sole cause of poor crop production has been political; there have been droughts, but only a small portion of the poor count

In fact, since the 1970s, the almost sole cause of poor crop production has been political; there have been droughts, but only a small portion of the poor countries have been affected by them at any given time. The most common causes have been either the gov't cutting off supplies to "rebels" or politicians beholden to poor urban masses holding down food prices so much that farmers can't sell their crops for enough to break even, so they grow only enough for themselves (or both together, with other stupidities thrown in, like current Zimbabwe).