Unlike the United States, where Facebook friends, Meetup groups, and other online innovations successfully elected a candidate who (at least initially) lacked top-down support, the Iranian power structure has less compunction about snuffing digital democracy. Incumbent Mahmoud Ahmadinejad is widely believed to have shut down Iranian access to Facebook as soon as it was clear his opponent’s supporters were using the social network to organize rallies and motivate voters. Not that Mousavi’s 36,000 Facebook friends at that point would have led to the undeniable landslide the opposition leader would have needed to actually win—but the heavy-handed gesture hinted at what was to come. It was the opening salvo in a digital war with global implications, and a blueprint for the democratizing influence of the Internet.

Iran’s government counterattacked with a blockade, closing off the four Internet access routes it controlled, leaving just one pipe through Turkey for messages to breach it.

Now that Ahmadinejad has claimed victory, the blogosphere, Twitterverse, and the rest of the social-networking sphere is on virtual fire. Tens of thousands of messages per minute condemning the results as fraud are passing to and from Iran, as angry Iranians and sympathetic outsiders exchange datapoints, analysis, and on-the-ground coordinates. While only a small minority of these posts are from people actually organizing protests, rooting out provocateurs, or sending aid to victims of violence, it’s too easy to discount the more virtual interactions as trivial.

Ahmadinejad sure hasn’t. His regime is working hard to stifle protest without completely unplugging Iran’s telecommunications infrastructure. Their tactics: limit cell service to in-country only, shut off text messaging, block transmissions to and from Facebook, and even shut down access to Friendfeed, a messaging aggregator extremely popular in Iran. They’re also identifying and then blocking messages from offending users and Web sites.

Iran’s Internet-savvy youth have fought back, however, exploiting “proxy servers” to make their messages appear to be coming from different sources, and exchanging the digital addresses of the ever-changing list of servers still capable of transmitting packets. Iran’s government counterattacked with a blockade, closing off the four Internet access routes it controlled, leaving just one pipe through Turkey for messages to breach it.

One particularly aggressive opposition group responded by facilitating a “denial of service” attack on the Iranian government’s servers. All over the Internet, users of all nations can get easy instructions for how to install a small program that “pings” the offending servers so frequently that they crash, unable to handle the incoming requests. Of course, the problem with this strategy is that it also overloads the few, compromised pipelines into and out of the country.

The net result proves that the age of the totalitarian dictatorship is over. Pictures of protests, police violence, and the reality of life on the streets in post-election Iran manage to seep out through the social networks. It’s impossible for any American user of Twitter to remain focused on the iPhone’s new features with this much real world life-and-death stuff crowding the inbox.

Most observers of the Twitter-fueled revolution rightly point out that this activity is at its most effective when it actually mobilizes real humans, puts bodies on the street, and gives dissidents the opportunity to organize successful retreats. Digital dissidence alone is easy, and easy to ignore.

But I think it’s also too easy to underestimate the real power of the Internet to provide more than information. On the Internet, content is not king—it never was. The value of Tweets right now is less the information they contain than the solidarity they promote. Like civil-rights protesters who sang rousing hymns as they were carried off to jail, Twitterers are bearing witness to what’s happening around them, and calling out into the darkness of cyberspace for confirmation. I’m here. You’re here, too. We are present.

Twitter, for all its faults, and the Internet, for all its insubstantiality, nonetheless serve as the strands of an existential telegraph. By resisting those who would censor history in real time, those flinging messages into the ether are demonstrating their freedom of speech—or, rather, their freedom to speak in spite of all efforts to the contrary. This mere gesture of freedom—the ability to connect to others and confirm one’s experience of the world—is what social networking is all about. While this may or may not be enough right now to topple an unjust government, the opposition, in demonstrating that this freedom is now a permanent right, has already claimed victory.