We've seen the incredible potential for technology to empower citizens and the dignity of those who stand up for a better future," said President Obama on Tuesday night, after he had just come off the phone from speaking to Egypt's embattled leader, Hosni Mubarak. To which one can say: yes and no. For the sense in which Mr Obama is correct may be quite limited. Undoubtedly, it is much easier to organise a demonstration than it used to be. You can call people from your mobile phone, send text messages, use Facebook, dispatch a tweet to your friends or fire off email messages. We are all connected now.
But also note what the head of police in Iran, Esmaeil Ahmadi Moghaddam, is doing. A few days ago, he proudly announced the launch of cyber-police units throughout the country to confront internet crimes and to counter social networks that spread "espionage and riots". The police chief said the cyber-police would take on anti-revolutionary and dissident groups who used internet-based social networks in 2009 to trigger protests against the re-election of President Mahmoud Ahmadinejad. "Through these very social networks in our country, anti-revolutionary groups and dissidents found each other and contacted foreign countries and triggered riots." Iran is not going to put up with that, he was saying.
So the technology to which the US President was referring is available equally to friend and foe. Take the mobile phone, for instance. The Egyptian government had a crude answer to all this potential-for-technology-to-empower-citizens stuff. Once the demonstrations became serious, it swiftly closed down all mobile phone services. Only yesterday did mobile phone communications begin to come back. In fact, governments don't have to shut down the whole mobile network; they can content themselves with switching off a single city or even parts of it. And while News Of The World journalists have proved adept at hacking into voicemail messages, many authoritarian governments can do better than that. They can use technology that allows them to interrupt the delivery of text messages that contain what they consider to be suspicious words.
There is a further aspect of mobile phones of which organisers of demonstrations need to be aware. Your location can be established by joining up the "lines" between local base stations. This is not an obscure technique. As Evgeny Morozov points out in his important book, The Net Delusion: How Not To Liberate The World, published last month, mobile companies have strong economic incentives to improve their location-identification technology so that they can sell geographically targeted advertising. If businesses can use it, so can police forces. When you are standing in the middle of Cairo's Tahrir Square, squashed among thousands of demonstrators, with your mobile in your pocket, switched on, you are not necessarily as well hidden or anonymous as you might wish.
Mr Morozov gives a frightening analysis of how authoritarian governments can harness the new technologies of the internet age. Social networking sites, for instance, make it easy to find one's friends who are already members, but cyber-police can use the same facilities for their own purposes. Nor do authoritarian governments try to do everything themselves. They force the companies that run the internet to police the web according to broad guidelines. This is the way Chinese censorship is going. In its essence, it is not so very different from the way in which the US Government went about putting pressure on companies that extended financial services to Julian Assange's whistleblower website, WikiLeaks. From the point of view of the authorities, the nice thing about this is that the companies get blamed, not them.
Take one of the internet's neatest ideas, crowdsourcing. Wikipedia itself is an example. It calls itself the free encyclopedia that "anyone can edit". Crowd-sourcing is a call for anybody who wishes to supply information or suggest solutions to problems to do so. But this same technique can also be used for the purposes of censorship. The government of Thailand, for example, has set up a special website urging people to inform on anyone criticising the monarchy. It has also established an internet security centre to co-ordinate the blocking of websites deemed offensive. On its first day of operation the centre banned nearly 5,000 sites. In Saudi Arabia, citizens are encouraged to actively report "immoral" sites for blocking. The beauty of this approach for repressive regimes is that they can claim they are merely responding to public opinion.
So what counter-measures are available to militant citizens of repressive regimes? Sensitive data can be encrypted. Another response is something I do anyway but not for reasons of security, which is to use a voice-over-the-internet technology such as Skype. I hadn't realised that our calls to our son and daughter-in-law in Japan using Skype would be difficult to bug.
Third, and I borrow this from Mr Morozov, you can use a software system such as "Tor", which protects your privacy by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents somebody watching your internet connection from learning what sites you visit, and it prevents the sites you visit from learning your physical location. Tor is free software and describes itself as an open network that "helps you defend against a form of network surveillance (known as traffic analysis) that threatens personal freedom and privacy, confidential business activities and relationships, and state security". Think of this, argues Mr Morozov, as surfing the internet using an anonymous network of helpers who fetch all the websites you need and thus ensure that you yourself are not directly exposed.
Two observations arise from these suggested responses to state surveillance and censorship. What is being discussed is a species of arms race. These techniques are weapons of a sort. When one side makes an improvement, the other side must match or exceed it. Moreover, all these techniques, whether offensive or defensive, are of as much interest to terrorists planning bomb attacks against targets in the West as they are to participants in protest movements.
This is why President Obama's optimistic statement about the technology that empowers citizens who stand up for a better future should be qualified. For it is also a technology that empowers authoritarian governments. It is only an unambiguous good in a wholly peaceful setting.