ON APRIL 6th Wikimedia France, the local chapter of the Wikimedia movement that runs Wikipedia, put out a rather strange press release. It alleged that it had been contacted by the Direction Centrale du Renseignement Intérieur (DCRI), France's domestic spy agency, which was unhappy with an article on the French-language version of Wikipedia about Pierre-sur-Haute, a military radio base run by the French air force. The spooks wanted the article amended to remove what they claimed was classified information. When the Wikipedians refused, the DRCI is alleged to have hauled a French Wikipedia editor into its offices and forced him to delete the entire article, on pain of immediate arrest. Instead of hiding the information, this made the story spread around the world—a textbook example of what internet aficionados call the Streisand Effect. Named after the American singer and actress Barbra Streisand, the Streisand Effect describes how efforts to suppress a juicy piece of online information can backfire and end up making things worse for the would-be censor. Ms Streisand inadvertently gave her name to the phenomenon in 2003, when she sued the California Coastal Records Project, which maintains an online photographic archive of almost the entire California coastline, on the grounds that its pictures included shots of her cliffside Malibu mansion, and thus invaded her privacy.

That raised hackles online. The internet's history is steeped in West Coast cyber-libertariansim, and Ms Streisand (herself generally sympathetic to the liberal left) was scorned for what was seen as a frivolous suit that was harmful to freedom of speech. As the links proliferated, thousands of people saw the pictures of Ms Streisand's house—far more than would otherwise ever have bothered to browse through the CCRP's archives. By the time a judge eventually threw the suit out, Ms Streisand's privacy had been far more thoroughly compromised than it would have been had she and her lawyers left the CCRP alone.

A similar thing has now happened to French intelligence. It is hard to imagine that many people are gripped by the intricacies of French military communications. Had the DRCI simply kept quiet, then the offending article would probably have languished in perpetual obscurity. Instead, the restored article became the most-viewed page on the French version of Wikipedia and was also translated into other languages. And the whole affair ended up being covered in English-language news sources as well. Such as, ahem, this blog post.

Correction: The original version of this post wrongly stated that the press release was issued by the Wikimedia Foundation. In fact it was issued by Wikimedia France, an independent chapter of the Wikimedia movement. This was corrected on April 17th.

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