The author might be underestimating the NSA's technical ability. The logic here is that each person has ~300 friends, and three hops is 300 x 300 x 300 = 27 mil

The author might be underestimating the NSA's technical ability. The logic here is that each person has ~300 friends, and three hops is 300 x 300 x 300 = 27 million. This is a big number, but the NSA doesn't have to give the same scrutiny and technical resource to each person. It's well known that most of the connections won't be interesting and there are methods to reduce the size of the list. Which brings us to the author's dismissal of pattern recognition. Statements like "A pattern recognition algorithm would come up with “young Saudi men” as the closest heuristic for the 9/11 bombers" are equivalent to "I've designed a bad classifier in my head and I'm telling you how wrong it would be". The NSA has more than a few smart people on this and they are probably working all the harder due to so much public attention. Algorithms can get very sophisticated with a sufficient amount of data and processing cores. The reality is that the NSA doesn't have the technical capability to find meaning in billions of communications. But they aren't stupid either. The scale of their data isn't going to hide us. Whether or not they'll use the data responsibly is another question.