One thing I think Dan Brown does too much is to make the most in-obvious person the bad guy. The same in A&D. Up until the car bomb I thought the NASA-boss was behind the whole thing (which was the point) but after that I started to suspect Pickering. Having Pickering killed in the car bomb and have Tench behind the whole operation would have been the obvious choice. Dan Brown tries too hard to avoid the obvious choce to the extent that the in-obvious choice becomes the obvious choice, just because it's Dan Brown.
But the story was good and interesting. And I liked that the senator got what he had coming.