To test, I did a search for "Tiananmen" in English in my hotel room; in English on a computer in an Internet cafe; and on Google's Chinese site, as well as Chinese search portal , using Chinese characters.
The first several pages of Google and Yahoo results in the hotel search were dominated by images from the 1989 protests, particularly the iconic "Tank Man" photo, which shows a young man standing in the path of a line of tanks. Links, for the most part, worked fine.
In the Internet cafe (which was, ironically, across the street from Tiananmen Square), the same searches produced two photos from the protests--one of Tank Man and one of wounded protesters--as well as several blanks on the first page of results. Attempts to go to page two severed the connection to the server.
On Google's Chinese site, nothing was blocked; the results appeared to be edited instead. Out of 27 pages of images produced on a Google search, there was only one image from the protests: a shot of the "Goddess of Liberty" statue facing the supersize painting of Chairman Mao at the entrance to the Forbidden City. It was on page 14. No image of the riots appeared and there were no blanks indicating a blocked image. There were a lot of vacation photos, though, and shots of college kids hamming it up in front of the Great Hall of the People.
On Baidu, no images from the 1989 events came up.
If the experiment is any indication, the Great Firewall of China is more thorough than I thought. It keeps sensitive information off of the sites most residents will use. Meanwhile, it makes accommodations for foreigners.
It even seems to discriminate between different types of foreigners, or at least their access points. Many of the news articles and videos critical of the government's handling of Tibet or Taiwan that don't show up in the Lonely Planet-style Internet cafe pop up fine in my French-owned hotel.
In fairness, the West seems to agonize more over Tiananmen than Chinese residents. One person I spoke to--a Chinese IT executive--said most people know of the events there, but are far more interested in the rising standard of living that has occurred in the past several years. There weren't a lot of hand-wringing editorials about the Apaches during Manifest Destiny, after all.
But the clean sweep does show the potential for altering history in the Digital Age. Limit information about past events and they can become viewed differently in the future.
If there's a bright spot, it's that it won't likely be easy for authorities to keep up. For one thing, more people are studying English here than before. New media isn't easy to police either. On an English search in the cafe on YouTube, two Tiananmen protest videos came up, but clicking on them severed the server connection.
Tiananmen through video
But search in the cafe on less popular Veoh Networks and a video called Tiananmen Not Forgotten pops up. The short film, which contains music but no dialog, consists of clips tracing the early rise of Mao in the 1940s on through to the protest and the bloody crackdown that followed. It's choppy, but so is a version of "The Star Wars Kid" on the site. If there were a window in the cafe, I would have been looking straight at the spot where the violence happened.
Similarly, on video-sharing site Grouper, clips of the riots set to music comes up. There's no dialog, but the place is tough not to recognize. To up the ante, I searched on "Tiananmen Massacre" and the clip still came up. (However, searches on a few Chinese-language video portals didn't yield results.)
Grouper also serves up videos of the Dalai Lama that cause YouTube to mysteriously stop working.
Audio gets through as well. On the BBC, an article on the Dalai Lama doesn't come up, but you can download an audio clip of the same interview.
And let's hear it for unintended consequences. An image search for the Dalai Lama on Google yields only blanks. But a site called Dalai Lama T-Shirts and Gifts--which displays pictures (on T-shirts) of the Tibetan leader--comes right up.
With text, the censors seem to do a much more nuanced job. Potentially objectionable links from well-known sites are blocked, and they do have a knack for differentiating between "objectionable" material and harmless stuff.
Links on Wikipedia culled in searches on "Tibet" and "Dalai Lama" do not come up. Of course, Dalailama.com, the site for the office of the Dalai Lama, is blocked. By contrast, a humor column entitled "10 Things You Might Know about the Dalai Lama" shows up.
The only search term that's completely nuclear on any site is unambiguous Falun Gong. Type that in and the computer goes dead. You don't even get links--the server times out right after you hit enter.
And TV? The censors just might be listening. I had CNN going in the background while typing this story. The network served up a story on civilian and military clashes in nearby Myanmar (domestic protests have become a serious issue here in the countryside). Right after the story started, it went blank. It came back at the start of a segment on the new cartoon L'il Decider.
It's probably a coincidence, but I don't think I've seen a TV do something like that in years.