How many times has the pervasive electronic surveillance that we live under stopped a terrorist attack? This is considering that the reasoning repeatedly given for enforcing this policy is that stopping the threat of terrorism is more important than every other aspect of society.

  • 2
    Are you asking specifically about the United States?
    – divibisan
    Mar 25 at 15:36
  • 2
    The actual answer to a question like this may be unknowable; more than half the point of having a bouncer in a club (as a different example) is to give people reasons not to start something in the first place. But how do you measure fights (or terrorist attacks) which did not happen at all because it was less likely to be successful? (Note: I am not saying that all preventative measures are effective or justified, just that the impact is sometimes difficult to measure.)
    – Jedediah
    Mar 25 at 16:05
  • 3
    @Jedediah I wouldn't say it's unknowable, but it may be classified. Certainly there might be a deterrent effect, but the use of the word "stopped" implies that it's asking about cases where an attack was prevented due to some positive action (disrupting a cell, arresting a terrorist, beefing up security in a specific place). These are definitely things that can be quantified, though it's possible that most of the objective information is secret and unavailable to the public
    – divibisan
    Mar 25 at 16:13
  • 3
    What country are you asking about? I'm in the US and don't feel like we have "pervasive" surveillance. I don't think there are many cameras in my suburban neighborhood, execpt maybe for traffic light monitoring.
    – Barmar
    Mar 25 at 17:35
  • 2
    As many have pointed out, this question need clarity - which country, and what policy?
    – r13
    Mar 25 at 17:56

As others pointed out in the comments, a list of successes would not be published by all concerned agencies.

There is one example from Cologne, Germany. were information from the NSA was apprarently passed to German authorities. The German wikipedia text says so, as did news media and spokespeople at the time; the English one is shorter.

  • Please elaborate as to what, (if the dragnet's successes and failures are subject to little or no public review), would prevent an ineffective but corrupt dragnet agency from creating fictional successes to justify their own perpetual funding.
    – agc
    Mar 25 at 17:58
  • 3
    @agc, the information caused arrests and prison sentences. If one does not assume that the courts are also corrupt, there must have been substance to the accusations.
    – o.m.
    Mar 25 at 18:20
  • It wouldn't necessarily follow that courts need be corrupt to issue undeserved prison sentences with no genuine substance. It's possible that unbeknownst to the honest courts the compelling evidence used to convict is negligently incomplete or even bogus, (i.e. falsified by the corrupt dragnet agency), or that a merciful court must follow harsh statutory sentencing (or pre-trial holding) guidelines irrespective of what most judges consider just or reasonable.
    – agc
    Mar 25 at 22:06

Not the answer you're looking for? Browse other questions tagged .