The luddites food requirements didn’t provide them with popular support.
Similarly US agricultural output could be cut in half without serious negative consequences. Far more corn ends up as ethanol than our food and we export vast quantities of highly subsidized food to zero benefit. Hell ethanol production costs as much in fossil fuels as we get ethanol from it, it’s literally pure wasted effort.
Rational policy would create a large scale food shortage and then let market forces take over. We could have 10 years of food on hand for every American at way less expensive than current policy with the added benefit of vastly reducing the negative externalities of farming such as depleting aquifers.
Be careful with the assumptions you're making. A risk management strategy, for example, will often appear to be of zero benefit except in the case where shit hits the fan. We can stop feeding cattle, producing ethanol, and whatever else overnight in the event that something happens.
> Rational policy would create a large scale food shortage and then let market forces take over.
Well I'm just going to state that I'm _really_ happy that you're not the one in charge and leave it at that.