I always go back to one of my favorite shows of all time, Connections, and this scenario....I remember watching this back in the early 80s and it really was sobering to comtemplate, and that trap is now even tighter than ever.
https://www.youtube.com/watch?v=lKELMR6wACw
That is an excellent little video, theory of survival is mostly fantasy, and illusion when compared to the nuts and bolts reality of it.
This is part of why I love the prepper/survivalist movement, the more people who store food, then the better for our nation, the more millions of tons of long term stored food shoved back into the corner of our basements and closets, then the better for the big picture, in a worst case scenario.