Politicians think the public service is a literal genie, which will do exactly what they are told (but will screw up if they are given the wrong instructions). From within, everyone has a hammer, and they tell the people above them that every problem looks like a nail.

The NSA can do sigint, and data mining. Every problem requires lots of data, and if they have enough raw data they should be able to predict anything and everything. So the politicians give them more data, and the resources to process it.