Signals intelligence has become a cyber-activity

Eleven years ago Edward Snowden, a disgruntled contractor working for the National Security Agency (nsa), America’s signals-intelligence (sigint) service, fled to Hong Kong then Russia and revealed that America and its allies were sweeping up much of the world’s communications. Intelligence agencies warned that his disclosure would have dire consequences, as enemies found other ways to communicate. In the end it was not as bad as feared. Agencies could no longer access “all of the data they needed to see, or had access to before”, writes Ciaran Martin, then a senior official at gchq, Britain’s sigint agency. But they could still get “lots”, he notes. Indeed, enough to provide American sigint with the lion’s share of intelligence, including intercepts of communications, that showed in 2021 that Russia was planning to invade Ukraine, and how it planned to do so.