This is one of those documentaries that just seems to leave you wondering what in the hell we are thinking as a species. How we have gotten so far from our connection with actual life that a human being could concoct a way to feed a cow a grain based diet of corn, that is known to kill the animal, just long enough to fatten it for slaughter. To cut a whole in the side of a living cow to study which antibiotics can be used to keep it alive long enough to make weight for slaughter.
This film gives you the opportunity to listen to farmers discuss how their crops are the worst crap ever grown on US soil and how they know it but need the money and can't care what the corn is for. How they grow only corn, and corn of only one kind, that is not edible just to get the government subsidy check and can't even grow thier own food anymore.
King Corn brings home the notion that we are all complicit in this insanity... each time we buy a coke, shop the local walmart, eat that cheesburger, we are making an abstracted choice to continue on this course of lunacy. I guess that is key... that this is all abstracted away from a direct connection to us. We never see or smell the slaugher house, we don't live next door to the family working in the Chinese factory, and we have gotten as fat and blind as all our diabetic neighbors so we don't recognize the mess we are in.