[gordaco]

Sorry, but the very nature of a black swan makes it unpredictable, thus unstoppable. This is what advocates of privacy loss don't seem to understand.

A few days ago the front page of HN featured an article about the likelihood of getting a "bad guy" using this kind of surveillance. The conclusion was that mistakenly getting a "good guy" was about 10000 times likelier. Of course, you could argue that the article made some numbers up, but the calculations remain, and the deep fact is that, if an event is rare enough, false positives will outnumber the successes by quite a few orders of magnitude.

Which means a simple thing: PRISM and the like don't even fucking work when it comes to creating security. Yes, the next 9/11 could be tomorrow: but no amount of PRISM would prevent it, no matter how safe may it make you feel.

Preventive actions only work when the offence is common. It's not the case with terrorism. As scary as it may sound, terrorism is as out of your locus of control as getting hit by a thunder.