China, the world's most populous country, 1.3, 1.4 billion people, will in the next decade or so have to begin looking for people outside of China.What does this mean? China will have to become a much more welcoming society. It means that China will have to attract immigrants from other countries in order to slow the aging of the population.

Since the first Gulf War in 1991, the Chinese have been increasing their military budget roughly by 11 percent a year on average. There's no way that China will be able to sustain that sort of military expenditure. And then the most important reason is because of its population changes.

China, the world's most populous country, 1.3, 1.4 billion people, will in the next decade or so have to begin looking for people outside of China.What does this mean? China will have to become a much more welcoming society. It means that China will have to attract immigrants from other countries in order to slow the aging of the population.

China has its own Baby Boom generation. And China's baby boom generation, because of the size of China itself, is the world's largest baby boom generation.

Soon numbers of Chinese people will exit the work force, and the Chinese work force, which has already begun to shrink, will shrink in a vastly accelerated way. And so China's going to face huge retirement costs and Social Security costs, health care costs, related to this immense aging of the population.

As I set out to begin photographing Shanghai, I encountered the insider/outsider phenomena in the most personal of ways. You would walk into an old neighborhood in the center of city, and people would begin to point at you. People would begin to talk about you, spreading the word about the outsider who has wandered into their midst, look at him, he's got a camera, what's he doing, is this allowed, is this OK, how should be respond to him.

The reason the United States is not aging rapidly in terms of its demographics is because we accept people as newcomers to this society in numbers that far surpass any of our major peers or rivals.