From the USA Today article Bill would keep servers out of China we learn

Now, Congress is stepping in with proposed legislation that could hobble the companies as they plunge deeper into one of the world's hottest economies. This is Round 2 for Congress. Last year, it scrutinized and slowed other business deals with ties to China's government among oil companies and computer makers.

Rep. Chris Smith, R-N.J., is drafting a bill that would force Internet companies including Google, Yahoo and Microsoft to keep vital computer servers out of China and other nations the State Department deems repressive to human rights. Moving servers would keep personal data they house from government reach. But that also could weaken the firms' crucial Internet search engines. (Related: AOL tries to speak Chinese.)
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Google last month launched Google.cn, a version of its No. 1 search engine that prevents Chinese residents from seeing, for example, photos of tanks confronting Tiananmen Square protesters in 1989. Also last month, Microsoft acknowledged shutting down a blog run by a Chinese journalist critical of the government.

Last fall, Yahoo acknowledged giving information to Chinese officials that led to a 10-year prison sentence for a journalist accused of divulging state secrets. Last week, Reporters Without Borders, a journalism group critical of Yahoo's cooperation with Chinese officials, accused it of working with the Chinese government in another case that led to a dissident being jailed. Yahoo said it was unaware of the case.

The companies say they are unhappy with the restrictions yet must honor local laws.
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Google's site launch came days after it rebuffed a U.S. Justice Department subpoena demanding that it turn over data on how millions of users search the Internet.

In contrast, Yahoo, Microsoft and America Online all cooperated with Justice.

Since this affects my day job I won't comment on it other than to say I find this entire debate very interesting. I will mention that unlike the USA Today reporter who wrote this story I'm not sure that the U.S. government's interest in the IBM/Lenovo or Unocal/CNOOC deals last year is comparable to the current efforts by members of congress.