[Nadya]

>One of the major points made in the article is that nobody hears about the attacks that get prevented.

The government would be shouting from the rooftops if they've prevented any attacks, if only to justify the surveillance. Pre-2015 there was a report that mass surveillance had not prevented a single attack. I'm not sure if that statistic is still true, but I imagine it is.

It does them no favors to keep the attacks prevented hush-hush, as it leads citizens to believe it isn't working at all.

Former NSA analyst, head of the spying program, calls it useless. [0] And more information/people-in-the-know [1].

[0] http://dailycaller.com/2013/06/10/what-do-they-know-about-yo...

[1] http://www.washingtonsblog.com/2013/07/the-fact-that-mass-su...