For those old enough to remember, it was common for people to build bomb shelters during the cold war, most dug into a basement crawl space or placed underground outside like a typical tornado shelter. There even was a movie about a family who mistakenly though a nuclear war was upon them and spent years in their shelter, then emerging into a world they didn't recognize. It's not, however, as though home builders need to start thinking of including shelters as options, but there is a thriving business in bunkers. CNET reports:

Now there's second boom (no pun intended) in demand, fueled by rising political tensions; worsening wildfire, tornado and hurricane seasons; and fears of terror attacks. Atlas Survival Shelters told Germany's Die Welt newspaper that it sold 1,000 shelters in 2017. Real-estate paper The Real Deal reports that Rising S Company, in Texas, saw 700 percent growth in international sales last year, mainly in Japan.

Bomb shelter makers tell me customers range from Silicon Valley's tech billionaires to working-class homeowners who want a safe place to hide in case of disaster.

"They don't just have to be for an apocalyptic situation," says Ron Hubbard, founder and CEO of Atlas Survival Shelters, which offers about a dozen types of shelters. "Here in California, with all the wildfires we have, that's actually our No. 1 concern right now."

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