[Beldin]

I've encountered this statement before. Without reading the article, here's the argumentation I heard:

Basically, the perpetrators were already known - there basically was already (close to) enough information to foresee serious problems (in hindsight * ), just no one connecting the dots. Adding mass surveillance to this doesn't make things easier: signals were already swamped under, that's not going to improve just by getting more data. Rather the opposite.

I don't know how this argumentation squares with the facts. But if the intelligence problem was "failure to connect dots", getting more "dots" is not a solution.

* also, hindsight is 20/20.

[specialist]

I've read many scathing critiques of intel services preferring SIGINT over HUMINT. Hard to disagree.

[marcosdumay]

SIGINT doesn't imply on mass surveillance, and HUMINT doesn't imply in targeted actions.

[specialist]

And yet that's what happened.