I WAS in front of a computer when the Twin Towers went down. The morning light flooded Charlie's tiny studio apartment kitchen where she had parked her computer desk in a spot that another person would use for a breakfast nook. "Holy shit," she said. "Look at the Washington Post!" I stared blearily at the monitor, coffee mug in my hand, and saw pictures of smoke.

Charlie continued clicking and clicking on news. It was everywhere: live streams and up-to-the-second photographs of the towers as they burned. One had fallen. Then the other one did. That morning we consumed hundreds of images and lines of electronic text, at the edge of a future I couldn't fathom. Shit was going to happen, that's all I knew.

My phone rang an hour later. It was Ed, whose plane from Japan to San Francisco had been diverted to Vancouver. No planes were entering or leaving U.S. airspace. What happened in geographical space was just the thin end of the wedge. Shifts more dramatic than anything I could have imagined occurred on our electronic communication networks. The phone system and the Internet formed a new ground zero, a place where "fighting terrorism" became a force more socially disruptive than terrorism itself.

In the weeks that followed, flags and half-baked, vengeful ideas spattered the mediascape online. ISPs allowed the government to install "carnivore" devices on network backbones, thus allowing the government to eavesdrop on everybody's Internet traffic. Passage of the USA-Patriot Act allowed law enforcement to send secret subpoenas to online service providers for information about their customers.

The mainstream media censored itself. Those of us critical of the U.S. policies that led to the attack literally whispered to each other about it. We were afraid to say what we thought of the government crackdowns. I thought everyone was going insane until I discovered Declan McCullagh's "politech" email list, where people were talking openly and irascibly about government crackdowns on civil liberties online.

Something changed the Internet forever during the surreal years after the attack on the World Trade Center when we went to war with a country whose citizens and leaders had nothing to do with what happened on Sept. 11, 2001. Data mining was weaponized. The ability to track hidden information patterns in vast piles of unsifted data, once the purview of obscure academic articles and some startups with weird names like Inktomi and Google, became the touchstone of government efforts to track down terrorists.

If a lack of intel is what allowed the terrorists to get us, then by gum the spooks were going to get as much intel as they possibly could. As a result, you got John Poindexter pushing misguided programs like Terrorism Information Awareness (TIA), which would allegedly be a giant computer operation where all the data in the universe would be crunched and "patterns" would emerge to lead government agents to dens of bomb-making bad guys. It also led to the NSA's now infamous (and probably illegal) surveillance of all the telephone and Internet data passing through AT&T's wires—as well as the wires of several other major network providers.

Both of these programs rely on the idea that you can find a terrorist needle in a haystack of data. And both were made far more dangerous by the rise in consumer products like gmail, flickr and myspace—giant databases of personal information, often tagged with keywords for easy searching. As many pundits (including myself) have said, we're creating our own surveillance treasure trove. But what that analysis leaves out is something near and dear to the American spirit: The people have weapons, too.

It isn't just the government that can turn data mining into a weapon. The citizens can do it too, often better. And so, the years since the 9/11 attacks have witnessed a blooming of what Dan Gillmor calls "citizen journalism." When the mainstream media wouldn't report what was going on, people turned to alternative sources of news, including online sources. Bloggers became the new investigative reporters. Bloggers like Jake Appelbaum went to Iraq, shot pictures and wrote about what they saw.

The groundwork laid by these subversive data miners continues today. The community of online journalists and researchers revealed that an AP photo of the fires in Beirut had been doctored. Bloggers sounded the alarm when upstart photographer Josh Wolf was arrested for refusing to hand over to police pictures he'd taken of a G8 protest in San Francisco. It's no accident that the rise of blogging coincides with the rise of government surveillance online. The people are watching, too.

Annalee Newitz ([email protected]) is a surly media nerd who is watching the watchers.

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