Food has more to do with capital and commerce than anything else. The inefficiencies of consolidated global scale distribution require squeezing every penny on the production side.
Refusing protectionist trade policy became popular among the people who make these decisions, a trend which accelerated after the collapse of the Soviet Union. We're in the middle of a crisis which brought to stark light the lack of resilience created by this relentless focus on efficiency and productivity at any cost.
But this is policy, not immutable law. Markets do predictable things in the absence of trade protection, subsidy, and state investment, true; but they do predictable things in the presence of them also.
Today you have buyer cartels purchasing in bulk and fixing prices. They demand quantities and pricing that shut the market to most players.
I can’t buy lettuce in NY at retail because the supply chain from Arizona and California is fubar. Farmers in NY will be harvesting lettuce from high tunnels soon, but they don’t have access to markets and can’t scale.
The truth is that it makes horrible sense to ship crops to the US from anywhere outside of the US.
US agriculture policy is broken fundamentally. It is corn, soy, wheat. It is what is used as the feed stock for industrial food production. Basically, all the pseudo-food that lines your grocery store shelves. In the US, your tax dollars are used to subsidize the production of this "food" so that it is artificially cheap.