If Yellowstone blew up like it has before, human civilization would end as would our contribution to global warming. More than a band-aid!
No, nations do not have the means to feed their constituents in a nation ending disaster. It's easy to move food from Florida to California in a state sized crises, but the logistics of maintaining a just in case food supply for hundreds of millions distributed around the country? It's a safer bet to assume you'd die in the disaster than to convince people to plan for the future.
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