It sounds like you want to buy land based on an assumption that some kind of catastrophic event is going to happen. I think that’s a bad idea. Sure, some kind of catastrophic event could happen that would turn San Diego into the next Road Warrior movie, but if that happens, who knows how it would be in Ohio. Maybe worse. Trust me, Ohio has its own economic problems, and some serious sustainability issues.
Are you looking to abandon the urban/suburban hamster wheel and adopt a more agrarian life? The sustainability issues with that are even worse. Agriculture is pretty volatile right now and a tough way to make a living under the best of circumstances.
What much of Ohio (and many other states) offer is cheap real estate that is far less prone to the expansion and bursting of bubbles. The problem is, you have to live in Ohio.