Twitter

They were just three telegraphic, panicked sentences amid the mayhem in Cairo’s Tahrir Square on Feb. 2, 2011. “Very tense near museum now. We’re still blocking them but fatigue & injuries slowly catching up with us,” Mosa’ab Elshamy tweeted at 10:31 p.m. “More people needed.” Hundreds following Twitter ran to help. Watching the lethal battle unfold from my hotel above, I tweeted at 11:22 p.m., “Listening to gunfire and Molotov cocktails exploding outside my window. A violent chaotic day bodes ill.” Twitter, now a $23 billion company that hosts 500 million tweets a day, did not create the Arab Spring; exasperated youth did that. But the torrent of raw, enraged tweets rendered government media toothless, instead directing mass action by the minute, and helping to topple a 30-year dictatorship in just 18 days. After Twitter, no revolution will be the same again. Its epic drama is written on the fly, in tweets like this from Feb. 2 at 3:01 p.m.: “Plainclothes thugs (police) are on horses now, trying to storm Tahrir Square, with whips!” In the stunned aftermath, we were left with tweets like this from one Cairo woman: “My dad hugged me after the news and said ‘Ur generation did what ours could only dream of. i’m sorry we didn’t try hard enough.’ ” Sadly, her dad’s generation did not have Twitter. —Vivienne Walt