Another sweeping promise of the Mexican revolution was agricultureland for the landless and food for all. Yet half a century later, less than one-tenth of the country's acreage is under cultivation, much of it in the semi-arid north and much of that belonging to the controversial ejido collectives. Peasants are guaranteed a plot of land, but the farms are small, dry and often uneconomic, rarely exceeding twelve acres. Peasant families have trouble feeding themselves, to say nothing of providing food for a nation whose population grows by 3.5% annually.
Last year López Mateos approved a bold plan aimed at...