The dawn of the internet era brought with it great promises, the grandest of which was that tyranny would soon be a thing of the past. With information just a mouse-click away, the theory went, rulers could no longer control what their people thought, nor keep them in pliable ignorance. Freed by the anonymity of the chatroom, activists would use the web to find like-minded folk, organise their opposition and bypass state control of radio, television and newspapers. Thus would oppression wither and democracy flourish.

Fifteen years on, the promise is unfulfilled. “It’s a real cliché that the internet leads to more freedom,” says Julien Pain, head of the internet freedom desk at Reporters Without Borders, a human rights group. “When governments put infinite money on the table, when they buy the software, when they employ the staff, then it can be controlled like any other medium.”

And that is what China has been doing. OpenNet Initiative, a group of British and American universities including Harvard Law School and Cambridge University, reported two years ago that China employed “numerous state agencies and thousands of public and private personnel” in its battle to limit access to the web. “China operates the most extensive, technologically sophisticated and broad-reaching system of internet filtering in the world,” the report continued. “The implications of this distorted online information environment for China’s users are profound, and disturbing.”

The Great Firewall is a huge technological and ideological achievement. “Ten years ago,” Mr Pain says, “if we said that a state would be able to extend its own borders onto the internet, people would have laughed.” Now, he says, the barriers are up and countries such as Cuba, Vietnam, Iran, North Korea and Zimbabwe are looking on with envy. “The worst thing about China is that they have a new model of internet and it is spreading around the world,” he says. “We know that they’re exporting technology, but they also take a certain mindset with them, and that’s what’s most alarming.”

Early attempts to censor the internet were unsophisticated and easily circumvented, but China has developed an effective system for blocking sites that mention democracy, Falun Gong, Taiwanese independence and other forbidden subjects. Using a combination of checkpoints at the gateway to its national network and filtration by individual internet service providers, it prevents many web pages from reaching the country’s cyberspace. Others may clear the first hurdle, only to be ignored by search engines, which fail to index the offending sites or omit them from results.

More sinister is the country's effort to disrupt debate in blogs, chatrooms and e-mail messages. Chinese internet service providers use mail scanning software to intercept messages containing blacklisted words, and attempts to post blog entries containing these words will result in the writer’s web browser throwing up a warning and then closing down. It is possible to circumvent these controls with enough effort and technical knowledge, but most people have neither. For those who try, the risk is substantial: according to Reporters Without Borders, China has imprisoned 50 people for what they have posted on the web.

It is tempting to force all this into a Cold War template. In the West we have a democratic web, dedicated to political freedom, commercialism and barely restrained anarchy. Opposed to this is a heavily censored and centralised model of web access which is spilling out into Cuba, southeast Asia, the Middle East and parts of Africa.

There are, however, signs that the West is getting cold feet about its laissez-faire approach. Concerns about cyber crime, paedophilia, pornography, violence and terrorism are growing, and even though in most cases the internet merely offers a newer and more fashionable outlet for age-old crimes and vices, the clamour for more invasive regulation may be difficult to resist.

In fact, resistance may be the least attractive option. Allowing unchecked web traffic runs counter to the deep-seated desire for control felt by many governments, and not just unelected ones. Last year, the US Government outlawed online gambling and the EU indicated a desire to regulate YouTube and other video-based websites as if they were broadcast television. Such measures may seem relatively trivial compared with China's interventions, but they indicate a willingness to extend national boundaries onto the web. Western democracies may not like what China is doing in practice, but they seem to like the principle of nationally regulated cyberspace.

When multinational companies such as Google and Yahoo! set up shop in China and agree to abide by the local rules, they're keen to play up the optimism of the dot-com days, when the web was going to liberate the world. Censored information is better than no information at all, they say, and once people realise that they've missing something, they will become more curious and begin to ask questions. It's a good argument and it may eventually prove true, but in the meantime it looks as if we're learning rather more from the Chinese than they're learning from us.

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