10. Bureaucratic spies are hapless when it comes to technology
The CIA sponsors a venture capital firm, In-Q-Tel, to identify promising tech firms and invest in them. (Endgame Systems is one of the recipients.) It helps keep them up to speed, but it relies on outside contractors.
The NSA seems to be even more behind the times. When Michael Hayden became director in 1999, the computer systems and managerial structures were such a disaster that he launched an expensive project to update them called Trailblazer -- and outsourced it to SAIC, Booz Allen, and others. By 2005, Hayden had to admit that the project was years behind and hundreds of millions of dollars over budget and it was shut down, though not before having helped authorize warrantless surveillance. (http://en.wikipedia.org/wiki/Trailblazer_Project)
According to Wikipedia, a replacement project called Turbulence was then begun to attempt to mean the same goals in smaller and cheaper steps, but by 2007 it was also over budget and not meeting its goals. I haven't been able to find out what's happened since, but I have to imagine that the NSA is even more dependent on its contractors and no less of a mess.
So the idea that these guys might actually have an operating system of their own, and be able to keep it secret and hacker-proof, it kind of a laugh.