How will California survive the end of America’s empire?

The question might seem hypothetical, but I found it inescapable last month in Rome, where I ran a global forum on the future of direct democracy. Our forum’s mission was hopeful: Hundreds of participants, from 80-plus countries, discussed how to democratize the world’s democracies.

But each morning, I encountered the less-hopeful remains of fallen empires.

To reach Rome’s city hall, the conference site, I had to walk up Capitoline Hill, passing two ancient monuments, each of which inspired a different thought.

The first monument, the Colosseum, seemed less special with each viewing. What’s the big deal about a dilapidated old stadium known for violent spectacles? Los Angeles and Oakland have similar coliseums today.

But the second monument, the Roman Forum, felt profound, its layers of ruins serving notice that no regime and no republic lasts forever.

Still, the Eternal City’s enduring lessons lie not in the ends of eras but in how people respond to those ends.

As Rome resident Matthew Kneale’s book, “Rome: A History in Seven Sackings,” shows, the oft-conquered Romans have rallied after some defeats, while turning against each other after others. But, he writes, Rome has survived because Romans eventually “shrugged off catastrophes and made their city anew.”

Californians can’t match the history of the Romans, but we too have been shaped by apocalypse. For all our state’s booms, California has mostly been fashioned during busts, when we had to reassess. Our state government’s progressive structure was created by San Francisco earthquake survivors while their city lay in ruins. Today, Californians from Redding to Santa Rosa to Montecito wrestle with the decisions that come after destruction from fire or mudslides. Do we stay? And if we do, do we rebuild the way it was, or do something different?

For all California’s experience with disaster, the soon-to-come end of the American empire — accelerated by crushing debt, faltering defense alliances, trade wars, racial resentment and that Nero in the White House — will test the state like never before. We are accustomed to being the richest part of the richest country, playing in a global economy that runs on our money and our rules. How will we respond when we lose that?

Will we be drawn into a polarized America and ape its violence? Will we quietly accept diminished prospects? Or will we come together, and find a distinguished place in a less American world?

Rome is a great place to think through such questions, because it has a young, forward-thinking government. Led by 40-year-old Mayor Virginia Raggi, Rome is run by an internet-based party called the Five Star Movement, which uses an online program to determine its agenda.

It’s unclear whether Five Star can reinvent Roman democracy with digital platforms or whether it will fail like other populist movements. But it was refreshing to watch its young members try.

Unfortunately, each day’s optimism lasted only until I returned to the hotel and turned on CNN. The screen conveyed America’s late-empire awfulness, and again posed that question: How will California get through this? The Palo Alto psychology professor on TV embodied the Californian predicament. Christine Blasey Ford struggled to maintain her dignity in the face of the American meltdown.

It looked like opera, with the tenor Brett Kavanaugh singing his angry arias about the maiden he claims he did not violate. And couldn’t they get younger actors for the chorus? Dianne Feinstein is a half-century older than the people running Rome. How could the New World of America have become so old?

One evening, Mayor Raggi took hundreds of conference attendees to a fashionable, open-air Roman nightclub with a canopy of cypress trees so beautiful even Monterey residents would marvel. Different areas of the club represented different ecosystems — marsh, forest, beach — while various bars offered different cultural styles — Japanese, Thai, Cajun, Tex Mex, Tahitian. There were hammocks, beds and even a maze of laurel bushes.

The place’s name? The Sanctuary.

California is proudly a sanctuary for unauthorized immigrants. But when empires fall, we all need sanctuary. Here’s hoping that California can eventually construct a new, diverse democracy atop the ruins of the American one.

Joe Mathews writes the Connecting California column for Zócalo Public Square. To comment, submit your letter to the editor at SFChronicle.com/letters.