The steel-man case could be:

> This will catch the x% of lone wolf terrorists who are too mentally unwell to use encryption and too unwell to hide their intentions.

> Without this, the relative increase in terrorism will cause strongmen to get elected who will just enact even more severe surveillance, among many other bad things.

> So it's not a choice between surveillance and no surveillance. It's a choice between relative levels of badness.

> This will also catch real criminals by listening to their close family members who have worse OPSEC than the criminals.