HEAVY BURDEN: The 4-2-1 pattern puts enormous pressure on the younger generation (CFP)

Behold the Americanization of China: fast food, plentiful portions, obesity and SUVs that eat up a whole hutong's pathway. Across several dimensions of society, the Middle Kingdom is hurtling toward the American standard—the good life promised to Chinese people by American films and television series.

However, it is plainly not sustainable. China is a country of 1.3 billion, and it must take the European path, bypassing the American consumer model of conspicuous consumption and unabashed gluttony. This won't be easy. Extraordinary though the last 30-plus years have been, China's wealthy has set an unrealistic example of the good life: a spacious urban apartment with an automobile and a parking space. Why is it unrealistic?

China's middle class, not yet 100 million, is predicted to increase to 700 million by the end of this decade. Let me not rest upon statistics and projections, certainly not in an enormous country like China. Instead, look to greater Asian society as a guide. Chinese academics have already identified several problems. For instance, Zhou Xiaohong, Dean of Social Science School of Nanjing University, said the middle classes in East Asian countries such as China and Japan cannot live like those in the United States, apparently because of the high populations and limited arable land.

Short reflection confirms this. Japan's densely populated society has accepted cramped living quarters and warmed to planet-friendly living. But this will be a tougher sell in China, where optimism thrives despite society's rocky adjustment to rapid change. In this race for wealth, several speed bumps must be heeded.

First, China's demographic problem is already grievous, especially its aging population and its medical and social needs. The 4-2-1 pattern of grandparents, parents and a single grandchild puts enormous pressure on the youngest generation to provide care for the old, while at the same time saving for the costs of marriage and child-care. China, despite its transformations, retains a traditional value system that typically looks to men to bear these costs. Potential wives, however, might not be entirely patient and understanding. An expectations-gap might arise, and China could witness declining marriage rates like those in Japan and South Korea.

Additionally, rising obesity will further threaten China's nascent social safety net. Obesity affects the young in particular, with over one third of boys overweight or obese. Contrary to trends in Western countries including the United States, obesity in China is positively correlated with wealth, bringing concerns that rising incomes might send obesity-related diseases soaring. As in the United States, ordering sumptuous plates of steak and buttered lobster might signal a certain social status, but it can lead to health and sustainability externalities that China can hardly afford.

From clogged arteries I now turn to clogged roads. As residents of most first-tier and second-tier cities know, China's urban infrastructure simply cannot fit as many automobiles as the urban wealthy would like. First, consider emissions. China's per-capita carbon footprint may exceed America's as early as 2017. Even rather modest GHG reduction targets cannot be met if every Chinese who can buy a car does buy one. China should instead look into some European countries' plans to make urban areas pedestrian-friendly, if not explicitly car-unfriendly.

Finally, highway construction outside of cities can be environmentally and socially disruptive in a country like China, where hundreds of millions of people still live by the hoe and sickle, as Chinese Academy of Sciences expert Lu Dadao recently pointed out. China surely needs better transportation infrastructure to reduce shipping costs, which are partly to blame for China's food inflation. What it doesn't need, however, are colossal traffic jams or highway fatalities. In sum, highways should be built for social and economic goals, and not for their own sake or the sake of private motorists.

In the terms I've just described, the hopes of China's middle class will be checked by the country's physical and environmental limits. It's a nice thought, but China routinely proves that it can push those limits with the sheer mass of its population. Every Chinese Lunar New Year's chunyun—travels back home for the traditional festival, every National Holiday week of tourism, and every Friday night on Beijing's highways gives us reason to consider the determination of Chinese citizens. Like Americans, they don't easily accept defeat or relegation to fixed social strata. Have-nots want to be haves. For Americans like me, that has come to mean a sort of material plenitude courtesy of Wal-Mart and similar retailers. For Chinese the last few decades, this determination has meant nights standing on a train, just to be home for the holidays. Soon, though, they will come to expect what Americans enjoy, or dare I say, suffer from, material excess, often as a symbol of status.

This, I wish to suggest, cannot be comfortably borne by China's environment and society. There is another model, as I've said already: the European model, in which quality of life is much less a material notion. To oversimplify somewhat, European culture stresses three major points: health, not wealth; stability, not adventure; and a fair-shake society, not a rat race.

To what extent can China adopt this? It's not fully clear. Americans and Chinese can be quite fond of the rat race, at least preferring it to the humdrum pace of European life. Second, like Americans, Chinese attitudes reflect a tolerance for wealth gaps that Western European countries have paired substantially in the post-war era. And in an era of enormous economic transformation, "I've got my health" will be little comfort to Chinese who notice their neighbors buying second homes by the seashore or sending their children abroad for university or even high school and middle school.

What, then, are China's planners to do? My best estimate is that, as with many things, great transformation will not be accomplished through just carrots or sticks, but through a national commitment to avoiding the Americanization of parts of Chinese consumer society. Such an effort would likely include the popularization or even glamorization of sustainable living. Public transport and better, smarter urban design, of course, but also a linking of China's environmental quality to the survival of its many natural and cultural treasures. Crucially, it's here that rising living standards and middle-class consciousness can be exploited. Materially satisfied Chinese are perhaps better able to appreciate the lost mystique of a Taishan Mountain despoiled by empty water bottles and half-gnawed ears of corn.

Skeptical that this can be done? You have reason to be. Chinese airlines, for example, don't even offer customers carbon-offsets sold by third-parties, citing lack of demand. Furthermore, the just-made-it crowd in China, having left behind their bicycles behind in the countryside or college, won't take easily to a slick single-speed and a chance to risk death in traffic during the daily commute.

We shouldn't expect it to be easy, since large national transformations aren't. The United States has never quite taken to the metric system, and most developed nations are helpless to right their entitlement and demographic problems. I have not much in the way of solutions to add here, and I am tempted to resolve only to highlight the gravity of the situation. Perhaps this frame will provide a fresh perspective.

The author is an American teaching Western philosophy at Tsinghua University in Beijing