[Slate] The Paris attacks weren't stopped by metadata surveillance. That hasn't stopped officials from saying it might have. They're wrong.
Since terrorists struck Paris last Friday night, the debate over whether encryption prevents intelligence services from stopping attacks has reignited. [...]
France—which rewrote its surveillance laws after the Charlie Hebdo attack earlier this year—has its own surveillance system. Both are in place, yet neither detected the Nov. 13 plot. This means they failed to alert authorities to the people they should more closely target via both electronic and physical surveillance. In significant part, this system appears to have failed before it even got to the stage at which investigators would need to worry about terrorists’ use of encryption. [...]
If the metadata dragnet works, that can happen even with encrypted communication. [...]
It all comes back to this triage, which is in significant part about how well the intelligence community uses that forest of metadata to pick whom it should target.
“Knowing who someone communicates with is metadata, not content, and most encrypted protocols (e.g. WhatsApp, Telegram, etc.) don’t change this,” Nicholas Weaver, a researcher at the International Computer Science Institute at UC–Berkeley explains. [...]
The terrorists who conducted Friday’s attack may well have been using encryption. But if so, it appears that the metadata dragnet failed well before agencies got to any encrypted communications.