The use of indiscriminate antibiotics in our food supply is causing all sorts of problems with antibiotic resistance, etc. Much of this problem comes from other countries, but ours is just as guilty.
Of course, the problem is that our low food prices are partially because we can use antibiotics, and thus pack animals closer together when we raise them (some have moral issues with this also, for understandable reasons).
If we wanted to avoid the catastrophes associated with antibiotic resistant diseases, what would we have to do?
a) research more antibiotics. This should be a continual process. This could be done pretty easily with our tax code and NIH grants - Making large percentages of R&D tax-deductible, funding research, etc.
b) ban the use of antibiotics in animals who aren't sick (testing would be necessary).
What happens then?
Testing would be expensive, as would disease verification. It would also be more expensive to raise animals in general.
Meat would increase in price, leading vegetables higher in price as people substituted. How could we mitigate food prices?
The easiest way to fix this would be to substitute vegetable production for meat production, but a lot of the land isn't convertible.
A better way may be a "long-term contracts" route - much of the arable land in America is already farmed. In South America, it is also farmed, but far less efficiently. Equipment in exchange for guaranteed food supplies at preset prices for an extended period of time would actually be valuable. That, and convincing Americans to eat a vegetarian meal or two per week. Vegetables are still more cost effective than meat, so we'd spend the same amount on food.