Consistently, Baidu has censored politically sensitive search results much more thoroughly than Google.cn.

It's much easier to force intermediary communications and Internet companies such as Google to police themselves and their users than the alternatives: sending cops after everybody who attempts a risque or politically sensitive search, getting parents and teachers to do their jobs, or chasing down the origin of every offending link.

The U.S. relationship with Bahrain is obviously more complicated than with Syria and Iran.

I haven't heard of any cases of anti-American blog posts being censored or bloggers encountering consequences for anti-American speech on the web in China.

On Apple's special store for the Chinese market, apps related to the Dalai Lama are censored, as is one containing information about the exiled Uighur dissident leader Rebiya Kadeer. Apple similarly censors apps for iPads sold in China.

It would be normal for anybody running a high-profile, politically controversial operation in China to anticipate worst-case scenario, and to do everything possible to guard against them.