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Google's decision to defy Beijing's rules censoring the Internet could be seen as an isolated event"”one company pulling out of China for a set of specific reasons. Certainly many other firms are acting that way, hoping to continue their pursuit of profits in the fastest-growing market in the world. But in fact Google's decision reflects important and expanding strains within China, and in its relations with the rest of the world.

"China places unique limits on information," Google CEO Eric Schmidt pointed out to me last week. It is the only major country with an elaborate, formal system of censorship that all information-oriented companies must accept. That's why in China, if you type the words "Tiananmen Square" or "Dalai Lama" into Google (or Baidu, the country's...