By Simon Winchester
If you have written a book suggesting that San Francisco could soon be levelled by a massive earthquake, you may find Californians a little reluctant to accept your message. Author Simon Winchester's idea that the US of the future could contain a number of ruined and abandoned cities has met a frosty reception.
California is one of the most quake-prone regions of the world
The first time that I ever saw San Francisco it was dawn, and I was standing on a mountaintop 50km (31 miles) away, and the city was gleaming white in the rays of the rising sun.
I was struck, more than anything, by its sheer fragility.
It looked so unlike the great cities of the East - New York, Boston - and places like Chicago, big and battleship grey and seemingly bolted onto the landscape with iron.
San Francisco seemed to cling oh-so-delicately onto its hills.
It looked, in a word, vulnerable. As we all know it is.
A little less than a century ago it was utterly destroyed in one of the world's most infamous earthquakes and the geologists who today study the San Andreas fault that runs underneath it predict that the time is more than ripe for a replay of that terrible event.
A greater than 60% chance, they say, of a big calamity in the Bay Area, sometime in the next quarter century.
Denial seems a powerful component of life in seismically active parts of America
This is not a message the local residents like to hear.
A week ago I was giving a talk in a bookstore on Market Street and saw a long white envelope on the podium, marked for me.
I imagined, optimistically, that it was a cheque. It turned out to be anything but: an anonymous letter, urging me to get out of town.
"You geologists," it began.
"If you can tell us we have three hours' warning, fine. But if you simply want to tell us that we live somewhere dangerous and that a quake might happen, well, we don't want to hear, thanks very much.
"Why don't you just go away and let us get on with our lives? We're happy here in California. Life is so darn good."
Denial seems a powerful component of life in seismically active parts of America.
So I am out on the road these days on a quasi-evangelical mission to try to reverse it.
And my pitch, or my sermon, goes like this.
In the ruins
In mature countries in the old civilisations of Asia, Europe and Africa, the big cities are, by and large, where they ought to be.
So London, Paris, Cairo, Beijing, Moscow, all thousands of years old, all in seismically stable places untroubled by terrible weather.
But by the same token these ancient countries are littered with the ruins of cities built where they ought not to have been built - Pompeii, Petra, Ayutthaya in Thailand, Heliopolis.
As tourists we cluster around these ruins, in awe. Ruins are part of our cultural inheritance, important for the perspective that they bring, reminders of our impermanence.
But America is a country without any ruins.
Maybe the odd ghost-town in Utah and Nevada, but basically no ruined cities.
The country is young enough to have set down its cities wherever it pleases, without ever stopping to ask if the world agrees.
And the world does not always agree.
It is a little eccentric to create a city on a swamp, six metres below sea-level, between a river and a lake
Which prompts me to wonder out loud whether - if one can imagine a map of America drawn up, say, two centuries from now - whether there may in fact be a litter of abandoned and ruined cities.
New Orleans, for example.
It is a little eccentric to create a city on a swamp, six metres below sea-level, between a river and a lake, in a part of the world afflicted by near-constant summer hurricanes. Might this not, one day, be abandoned to the elements?
And what of Tucson, Phoenix, Las Vegas, even?
There is no water there. And there is no great world tradition of building cities to last in the middle of deserts. So Phoenix may go the way of Petra, though it is a little difficult to imagine its ruins attracting quite so many tourists.
And then what of San Francisco?
A heresy, of course, to imagine it ever being abandoned and yet it does lie athwart one of the most dangerous tectonic plate boundaries on the planet.
Might it not be possible to suppose that some peoples of the future will wander, amazed, around the stumps of the Golden Gate Bridge, or the shell of the TransAmerica Pyramid and wonder - why did anyone ever choose to live here?
And so all in the American West will in consequence live happily ever after, earthquakes notwithstanding
This is where the audiences start to become restless, and a faintly hostile muttering can be heard.
But I try to still them with a soothing balsam. Why not take a leaf, I ask, from the one country that has learned to live with earthquakes for the past 2,000 years and that, of course, is Japan?
And with the sudden realisation that it is, after all, entirely possible to come to terms with earthquakes and survive, everyone in the room begins to nod happily and sagely and promise that yes, they will mug up on how its done in Tokyo and Osaka and Kyoto.
And so all in the American West will in consequence live happily ever after, earthquakes notwithstanding.
As the man wrote:
"Life here is so darn good. We're happy here. And that is what it's all about."
"So can I stay?" I asked.
"Sure," they said. "Stick around."
From Our Own Correspondent was broadcast on Saturday, 3 December, 2005 at 1130 GMT on BBC Radio 4. Please check the programme schedules for World Service transmission times.