Can anything twart "Large Terror Attacks"? Is there really a socioeconomical measure that can twart a determined attacker?
There will always be a cat and mouse game, it seems the trick is to not play the game in the first place.
To breach a wall, you have to construct a single ladder.
To protect against a ladder, you have to raise all of your walls.
This escalation is in fact the basis of al Qaeda's anti-Western military strategy -- to engage in assymmetric warfare[1].
The only reason they succeed is becomes on infrequent occasions law enforcement is even more incompetent.
The 9/11 attacks had many, many red flag warnings before they went down that were largely ignored. What's so unusual about people training to fly planes, but not take off or land, right?
The same patterns will be found here in hindsight.
Deep, pervasive surveillance will only flood already saturated information channels. What they need is less information of a higher quality, not more noise in the system.