Whatever the intent of the series (other than entertainment), it's a far cry from the book on which it's based. Essentially the only thing the producers used from the book was the general outline of the central character. Everything else is miles away from the novel, including what Martin Odum does. In the novel, he's left the CIA for moral reasons. In fact, the CIA has painted a bull's-eye on his chest.
The novel's pretty good, by the way.