The primary problem with this approach is "suffering accountability". When 85,000 people die of car accidents, there's typically no singular group or individual

The primary problem with this approach is "suffering accountability". When 85,000 people die of car accidents, there's typically no singular group or individual to blame for all the accidents, in total. With a terrorist act, there is a singular group or individual who is responsible for the suffering of multiple individuals, plus all the suffering of those who view the news around the attack and become fearful as a result. If we collectively perceive this group or individual could have reasonably been stopped, might we be likely tend to underestimate the costs of stopping them completely? When we underestimate the costs of "perfect" crime prevention, perhaps our expectations in those who need to stop crimes goes up. And maybe, just maybe, when law enforcement has high expectations placed on them, and their budget is limited, they might be more susceptible to fall into cognitive dissonance - literally believing they must stop all crime on a tight budget. I'd say, if these assumptions are true, mass surveillance becomes an option at that point.