Big Al:
I support eat local to; farm raised by a family not a corporation, but ag as an industry is a staple to the AMERICAN economy. What other economies do we have now? Steel, auto, etc.? There are intrinsic costs as use mention due to pollution; but how do we address those issues created from automobiles, smog, illegal dumping (City of Osage Beach) and know polluntants. The US economy has the cheapest food in world, despite high grain prices, high fuel and transportation cost we still do. We export more food than any other country especially pork and chicken, why because other cultures (hispanics, asians, and others) enjoy cheap commodity as well and are tranforming into more DOMESTICATED societies. So the question of feeding the world is applicable in it's own right, as nation, as a culture, as a farmer.
Good discusion!