One key takeaway. Any kind of backdoor or weakening of encryption creates a massive financial risk, by making payment systems inherently weaker and susceptible to industrial hacking. Doubly dangerous in the face of the exponential growth of cybercrime. My take: not only might weakening encryption not make us safer, it would almost certainly make us poorer.
Metadata, in particular, metadata which includes network interactions (who you phone, who they phone, and the overall properties of the calling network) can tell you a hell of a lot.
This also seems to be an area where governments can look for innovation in the tech industry. Germany tracks 420 potential extremists
and France about 1,400 (with a similar number of officers to follow them). Facebook tracks 1.2bn people around the world in real-time,
can predict how we are likely to behave and indeed trigger us to behave in particular ways. Would seem to suggest that cross-pollinating some of the software, processes and techniques from the internet ad industry to the terror threat might be a fruitful approach. (Of course, data scientist salaries in GCHQ/DSGE might not compete with those in Facebook