How many people can the planet fit?

Question: When you read the newspaper or watch the news, what issues stand out for you?

Stephen Walt: I think there are several. I think . . . I’ve already alluded to a couple. I think there is a sense . . . a growing sense that there are going to be limits to how many people you can keep on the planet, and how many people you can have living at a certain standard of living. And I think the major constraint there is environmental. The most obvious symptom of that is growing concern with global warming and climate change of various kinds; and the sense that we may not be able to stop that particular train before it goes off the cliff, you know if you imagine some of the more catastrophic scenarios. Does that end all life on the planet? No. But does it have very severe consequences for different parts of the world? I think that’s there.

I think we are going to see over the next 40 or 50 years a fundamental shift in the balance of power between what has been the sort of transatlantic access – Europe and America – for the last several hundred years shifting more towards Asia. The United States will be a critical part of that too; but again India and China much more so. I think third there is a . . . an issue of equality . . . an inequality on a global scale now which is compounded by the fact that increasingly, people who are further down the inequality scales are more and more aware of what their relative positions are. And again, the advent of global communications and things like that is starting to make it much more obvious to people. So we have at least, I think, a potential train wreck of different trends happening where India and China are developing. Their development is going to put greater environmental strains on the world.

They’re not going to want to remain in an undeveloped condition, right? The advanced countries like the United States are going to be concerned about what this all means. And everyone is going to be more aware of all of this simultaneously. So I think the potential for real trouble down the road is considerable. And I’d add one final little problem in there is the capacity for small groups of people to cause large amounts of destruction has gone up for a hundred years or so. You think about what you needed to kill 3,000 people in an afternoon. Well if you wanted to do that in 1900, you pretty much had to be a government with an army. But now of course 18 people or 19 people can fly planes in and kill 3,000 people in an afternoon or a morning. And if you marry that up with either biological weapons or some kind of crude nuclear device, again you could imagine terrorist groups or other non-state actors having much more destructive impact. And that’s, I think, going to be something we tend to worry about a lot over the next few decades.

October 8, 2007