What if the value of the dollar was suddenly worthless? (Jose Luis Gonzalez/Reuters)

It’s 2029, and the president says the United States will default on its loans and won’t join other nations in converting to a new global currency.

Treasury bonds that were once the gold standard — backed by the full faith of the federal government — have become worthless. Everyone is ordered to turn over his or her gold, including jewelry.

Overnight — literally — people’s retirement savings are wiped out.

The dollar has lost its almighty power at home and abroad. Inflation is soaring so fast that people spend their pay as soon as they get it. They can’t afford to save.

How would you survive in such a world?

That’s the question I kept asking myself as I read Lionel Shriver’s “The Mandibles: A Family, 2029-2047” (HarperCollins Publishers, $27.99). The novel is the Color of Money Book Club selection for this month.

It’s also an American economic horror story.

One of the lead characters is Florence Darkly, a Barnard-educated mother who lives with her teenage son in East Flatbush, Brooklyn. She’s barely able to eke out a living in this new world order.

The water supply is low, so showering is a once-every-few-weeks treat. Meat — any meat — is a luxury.

“She shunned ironing to avoid paying for the electricity,” Shriver writes. “To skip showers, she cultivated the pirate-style bandana into a permanent affectation at work.”

Florence’s two-bedroom home eventually has to accommodate 10 people, including her once-wealthy sister and brother-in-law and their three children, displaced from the home they can no longer afford.

Every trip to the supermarket “fosters post-traumatic stress disorder,” Shriver writes. Food is scarce and comes at a steep price. A cabbage, one of the more economical choices, costs $20.

I recommended the novel for another book club I belong to, Color Me Read. I thought you might like to hear how a couple of the members felt about it.

●“As a science-fiction reader since grade school, I find it interesting how dystopian novels so often reflect our fears. This is the first novel to my memory that looks at dystopia after an economic collapse.”

●“The author’s portrayal of how easily our lives can be upturned by a financial crisis was humbling, frightening, all too real. Seriously considering whether I should be building a bunker in the back yard and stockpiling water and gold bars. Definitely renewing my passport.”

This novel scared me, as well. It depicts a future I can’t say is impossible. So many of us are so comfortable that we ignore the fact that millions in the United States and abroad live under extreme financial conditions.

The Great Recession should remind us of how financially tenuous our lives are. It got bad for a lot of people. Homes were lost. Jobs once seen as secure weren’t. Retirement plans were upended.

Think about it: A lack of access to good and affordable health care is just a job loss away.

The recession may be over, but economic unease abounds. During one of my recent online discussions, an older couple with $1.5 million in savings fretted that they didn’t have enough for retirement.

With that backdrop, is the future Shriver imagines really so far-fetched?

Have you been following the news about Venezuela? There are riots because of severe food shortages. Electricity and water are rationed. The country’s currency is nearly worthless.

I’m a fan of scared-straight apocalypse fiction. The horrors of what can happen remind me to stay humble and to avoid being so self-righteous in my ability to manage my world — my money. I’m a good saver. But what if it’s not good enough? You can plan for only so many financial emergencies.

So I ask myself: Have I built a community of support wherein we could lean on one another?

Have you?

How would I react if I couldn’t find work and had to go without a decent meal, showers, toilet paper or the many other comforts I enjoy? Would I steal to feed my family?

Would you? And if you decide you could be capable of anything, might that instill in you more compassion for those less fortunate?

I read the book on my vacation. And while “The Mandibles” isn’t typical beach reading, what better time to be reminded not to get too comfortable or conceited about your financial status in life?

I’m hosting an online discussion about “The Mandibles” at noon Eastern time on July 20 at washingtonpost.com/discussions. Shriver will join me to take your questions.