This style of argument should not be allowed to carry the day in America, because if it does, the national security state will cease to be rigorous or accountable in any way. In Hirsh's telling, America's national security elites have presided over policies that coincided with the rise of a more dangerous Al Qaeda. But the answer is not to fire the people in charge for failing to competently reduce the terrorism threat. Rather, it's to empower them to pursue existing policy more vigorously.
We're supposed to accept the proposition that "NSA surveillance may well be the only thing that can stop the next terrorist from blowing apart innocent Americans, as happened in Boston." But NSA surveillance was operational long before the Boston bombing, and did nothing to stop it from happening. In addition, long before the bombing happened, Russian authorities warned the FBI that Tamerlan Tsarnaev should be considered a terrorism threat. Authorities hardly needed a comprehensive haystack to find that particular needle.
National security officials can be forgiven for arguing that a lack of terrorist attacks proves that they're performing ably and ought to be trusted with even more power... even as they argue that a rash of terrorist attacks proves the urgency of giving them more power. Those of us outside the national security state should know better. We should insist on more rigorous evaluations of counterterrorism policy. Insofar as it is possible, we ought to test falsifiable claims, and to let real world outcomes influence policy. A DailyKos diarist put it well:
...our national security laws have moved us to a non-falsifiable world. That is, a government official may claim that these policies have "made us safer" or a company spokesperson can deny involvement in the programs, and it is essentially impossible for us to determine whether their statements are true or false (or more broadly to know the extent of the surveillance programs: who is involved, how, and what they're doing). The key aspect to falsifiability is not that we care about something being true or false, right or wrong, but rather that we care that something can be shown to be true or false, right or wrong (or even some shade of gray). That gives us confidence that we can use evidence to guide our decisions and change course. When no evidence can be presented one way or the other, we exit the realm of the falsifiable.
Unfortunately, the secrecy that surrounds national security policy makes it impossible to rigorously test how effective NSA surveillance has been. National security officials would have us believe that this secrecy is itself needed to keep us safe. What cannot be denied is that secrecy facilitates the ability of national security bureaucrats to hide it when the policies they champion are working very poorly. If unprecedented NSA surveillance coincides with a rash of small terrorist attacks on the American homeland, the proper response is not to double down. It is to figure out why the counterterrorism policy we've pursued for the last ten years has failed, to fire the people responsible, and to try new policies.