Are we doomed?

Toward the end of "Collapse" you describe two crucial factors for determining whether or not a civilization will survive, and one of them is whether there's a willingness to discard unhelpful values. Clearly we have some values in this country that are very important to us, but some of them, like anathematizing family planning, aren't very helpful in this day and age.

You're right. One of the two or three key issues is discarding values dear to us, values that we held for a long time and that were important in the history of the United States but just no longer make sense today. The two traditional American values that I think -- that I know -- have to be discarded are, first, unbridled consumerism resulting from our sense of being in a land of unlimited resources. Historically the United States has viewed itself as the land of infinite bounty, endless fields of grain. But now we're in a world that does not have unlimited resources, and we have to come to grips with that.

And the other long-held American value is the value derived from the United States' relative isolation. George Washington in his farewell address warned Americans about the danger of entangling alliances, and for a couple of hundred years the United States was able to function well because we were separated by oceans from any country that might damage us. But now the oceans don't separate us from countries that could damage us. Now, even desperately poor countries like Afghanistan and Iraq can raise absolute hell with our economy -- as well as killing a few thousand people in the process. So the other long-held value with which we have to come to grips is our sense of isolation. We're not isolated anymore. We have to engage with the rest of the world -- not in order to be charitable to them but for our own self-interest. It's much cheaper to put a few tens of billions of dollars into world programs for public health and environment than to throw $150 billion into Iraq and $100 billion into Afghanistan, when there are about 20 other countries waiting to become the next Iraq and Afghanistan. We can't afford it.

But how exactly do you go about discarding an idea?

One can answer that two ways: first, by looking at countries that have successfully replaced or are successfully replacing dearly held ideas; second, one can ask what's going to replace -- for us -- unbridled consumerism.

I was a graduate student in the late 1950s and early 1960s in England, so I lived in England for four years. Those were crucial years in England because of the attempted British invasion of the Suez in 1956. That was the event that in effect convinced the British that they were no longer a world empire. And it meant a really painful readjustment for the British, to discard what had been really their guiding identity for a long time. And the British have struggled to find a new identity. But today it's becoming clear that Britain's new identity is the English-speaking country within Europe in a world where English is going to be the common language.

Now, as for us, what's going to replace consumerism will be the recognition that we have to live within our means, that we're part of the whole world, and that consumerism simply is no longer viable if we want to make a world that's going to make sense for our children. We have to live in such a way that we pass on a worthwhile world to our children. And that's a wonderful ideal that can replace consumerism, that will have to replace consumerism.

Have you heard of Michael Crichton's new book, "State of Fear," and its premise that a bunch of environmentalists are upset that their cause isn't getting the attention it deserves so they go around staging environmental disasters? Crichton has said publicly, as well as in his heavily footnoted book, that global warming is bunk -- which would be laughable were not the print run of his book one and a half million copies.

Everything you say is true. There are a couple of things to be added to it. One is that my previous book, "Guns, Germs, and Steel," has sold more copies than Michael Crichton's one and a half million, so I think my new book will get to more readers. And the other thing is that Michael Crichton is a very skilled writer of fiction. And fiction is, by definition, the telling of stories that are untrue. He's very good at that. And I'm a writer of nonfiction, which aims to be the telling of stories that are true.

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