I don’t fully understand this whole situation, but who cares if they cannot export, if they sell to the states that would be local produce, less cost in getting it to market should mean a profit? and maybe lower prices for consumers, making more demand for their product? If they got into farming a product just for subsides and perks of exporting etc then that was their foolish choice thinking they would always have those govt helps - and maybe they need to switch to a product of local need.
Have you ever been to Iowa?
Have you ever been to Kansas?
They are capable of producing far more than America can purchase. Development of export markets has enabled the vast acreage available to be productive.
We have the best fed dogs in the world. The American dogs are consuming the excess farm products.