There are legitimate reasons for governments to do sigint, but I think the burden of proof should be on them to show that increased sigint capability would have done anything to prevent this attack.<p>So far I&#x27;ve seen remarkably bupkis in terms of concrete reasoned arguments in this area. I&#x27;d like someone from e.g. the NSA or GCHQ to give a presentation in which they show that it is feasible to spot terrorist activity in an ocean of otherwise normal data and differentiate it from e.g. morons talking trash that they&#x27;ll never act upon, gamers talking about in-game terrorism, lesser criminal activity, non-criminal dissent, and other background noise. My strong intuition is that this is statistically and mathematically impossible and you&#x27;d drown in false positives, but I&#x27;d be open to a convincing argument if these agencies wanted to dignify the public with such an explanation.<p>Unless such evidence can be furnished, then all this mass surveillance data mining to &quot;stop terror&quot; amounts to a kind of modern superstition. Back in ancient times priests collected a lot of money from kings and from the public in exchange for entrail-gazing and astrological rites to guarantee success in battle or ward off a poor growing season. None of that crap worked, and I doubt that big-data entrail gazing works either.