People actually paid significant parts of their yearly salary to build, stock and maintain nuclear bomb shelters in their backyards...in places like Ohio.
Something like this [1] was just seen as mildly eccentric, not something that would get you institutionalized with severe paranoia.
1 - http://www.smithsonianmag.com/smart-news/this-1970s-undergro...
People, large numbers of them, actually believed (and it may have been true) that extinction-level global war was an accidental launch away.
What's even more interesting is the long-term vestiges of these ideas have hung around, but without nuclear war being on the horizon they've morphed and latched onto other scenarios: a Republican-Democrat civil war, the Rapture, Zombie invasion, Disease outbreak, etc. These aren't just old shelters, these are brand new.
http://alpinesurvival.com/survival-shelters-for-sale.html
http://www.popularmechanics.com/technology/engineering/archi...
Though, I'm always struck with how everybody wants to outfit their end-of-the-world bunkers with modern living room entertainment centers complete with cable TV, wi-fi and comfortable home-office.
In any other scenario, somebody who spends millions of dollars to build 7,500 sq ft of underground EMP shielded comfortable living area with hidden and barricaded entrance, independent filtered air and water and multiple years of emergency food [2] would be dragged into emergency psychiatric care.
But instead these scenarios are talked about openly on major news networks, reviewed in popular magazines, and I can buy these supplies commercial and off-the-shelf -- there's industries that exist to do nothing but feed this demand!
2 - http://www.costco.com/32,000-Total-Servings-4-Person-1-Year-...