Although data storage is certainly an on-going goal of the NSA, a more likely immediate use may very well be brute-force hacks of encryption, which is an extremely computation-intensive endeavor.
All modern communications are encrypted. The NSA is very interested in defeating encryption, and has a facility in TN engaged in the “High Productivity Computing System Program” that concentrates on that one goal. The immediate official goal of the program is to design a computer capable of petaflop speed – that is, one quadrillion operations per second.
Major progress on defeating encryption has already been made.
Note the mention of NSA “backdoors” in commercial encryption. Scary, isn’t it?
Of course, technology changes very quickly. New methods of encryption are being written all the time. The NSA will of course try to defeat any new methods of encryption. Assuming brute-force hacks, that is going to take considerable computer capacity.
With all due respect to Moore’s Law, there are limits to computational speed. That is, using conventional technology.
The new frontier may be Quantum Computing. A good video explaining the basics of quantum computing is here …
Before you assume it’s an entirely theoretical, consider that Quantum Computers are already being made.
The NSA manufactures it's own chips (as does Google and others who place a premium on security).
OK, the NSA has super-computers, is developing even more-powerful computers, has an unlimited budget, and operates in secret with little or no oversight. Why should I care?