you are suggesting former peasant farmers work for a pittance

Or, more precisely with the South American exmple: a few of them would continue to work for a pittrance, while the rest would end up without land and job and move to urban slums.

_{*Lunatic*, n.
One whose delusions are out of fashion.}

I do nothing of the kind. First of all, I haven't mentioned plantations. Second, plantations can very well be sustainable. Thirdly, I have said nothing about low wages. The lower costs would come from the reduced import duties and the increased efficiency created by such a move. Further, high wages in the agricultural sector (and in other sectors as well) are only possible, for obvious reasons, with a high degree of mechanisation (higher output, fewer need to share the agri-income). Even further, wages cannot become lower than they already are, as everyone who has those jobs moves as fast as they can, even if the alternative is a sweatshop factory job with very low wage.

Peak oil is not an energy crisis. It is a liquid fuel crisis.