A revolution online

So Ziada tweeted “everyone I knew.’’ Before long she heard from an officer in the security forces explaining it was all a misunderstanding: A popular soccer team was scheduled to parade through the streets, and police were there to keep order. “If not for the Internet, God only knows what would have happened,’’ she said.

Most democracy activists believe online technologies are their friends. In February, an Egyptian couple actually named their baby girl Facebook to honor the role the social media site played in catalyzing the popular uprising that led to Mubarak’s ouster. In Tunisia, democracy blogger Slim Amamou was able to switch on the Google Latitude app on his cell phone as he was being arrested, helping his friends find him.

But like any tool — or weapon — the same technologies can also be employed for nefarious ends. Crowd-sourcing can look a lot like snitching when a repressive government uses it to identify dissidents, as the Iranian government did following election protests in Tehran. If a Facebook account falls into the wrong hands it can instantly identify whole networks of activist “friends.’’ Twitter feeds, cell phones, and cameras can pinpoint a protester’s location, sometimes without their knowledge.

There are technological fixes — encryption, plug-ins, or other security measures — but they don’t always help. In Syria this week, police are storming into homes and roughing up suspected dissidents to get their Facebook passwords — a technique that human rights activists darkly call “rubber-hose cryptanalysis.’’