CYBER-CAFÉS were once a favoured tool of Western intelligence and security agencies. They were inconspicuous, cheap to establish and highly effective. Set up near an international summit buzzing with targets, or close to a mosque favoured by Islamist extremists, these facilities allowed their masters to monitor browsing habits, obtain targets’ logins and passwords, and plant spyware for future use. This was legal: consent was buried in the terms and conditions which users clicked on without reading. And in a neat twist, security-conscious people trying to avoid using their own computers favoured such places. Some would hop between cafés, unaware that all the convenient ones were run by the authorities.

Not any more. Edward Snowden, a fugitive former contractor for America’s National Security Agency (NSA) now living in Moscow, revealed the use of cyber-cafés to spy on the G20 summit in London in 2009. Now people are wary. In many countries the cyber-cafés have been closed. The staff who ran them have had to be moved (and in some cases given costly new identities). As a result, keeping track of terrorism suspects is now harder, spooks say.

The episode highlights one of the most important trends in modern intelligence work. Collecting electronic information is generally getting easier. It is hard to lead a completely non-digital life, and any activity using computers and networks creates openings for the watchers. An e-mail is as easy to read as a postcard for anyone with modest technical skills. With a few tweaks, mobile phones become tracking beacons and bugging devices. Most people readily trade private information for convenience. And hacking into computers can yield vast amounts of intelligence.

A lot of spying, however, has become trickier. It is much more difficult for intelligence officers to maintain secrecy and create fake identities. And high expectations of privacy, especially in the digital realm, mean that in many countries the work of intelligence and security agencies arouses outrage, not gratitude…

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