Keogh's heart is in the right place with this project. Doing a close, critical reading of a video game could be a very fruitful and useful endeavor, and Spec Ops: The Line seems like a game that could warrant such a treatment. Killing is Harmless, however, provides such a shallow, forced level of insight that I'd swear he was stretching to meet the page requirements of an assignment in an undergraduate literature class.
A vast majority of the book is spent simply describing the events of the game along with some obvious interpretation of the emotional cache of those events. I got the impression that I could have gained about as much insight into the game by simply playing it or watching a Let's Play as I did by reading Killing is Harmless. Keogh has no framework with which to critique the game: he vacillates between a personal, emotionally focused interpretation (when he wants to tell us that killing Americans made him feel sad), a vaguely intersectional approach (to explain why killing Americans might make an American more sad than killing faceless brown skinned bad guys), and a more literary approach (when he feels like interpreting a symbol). He also throws in a lil' token feminist critique whenever a woman dies. Brownie points!
There are a number of places where Keogh just doesn't do his research. He paraphrases snippets of conversations rather than quoting them and he forgets where certain pieces of intel (collectables within the game with expository audio clips attached) are located. They're small problems but they make it very clear that he doesn't hold himself to the academic rigor that he is ostensibly trying to emulate.
Keogh's interpretation of symbols is clueless. I cannot sugar coat that statement. Shortly after telling us about how he spent 12 years at a catholic school (which is how he recognizes the arcane quote "forgive them because they know not what they do") he comes across a significant statue. The statue depicts three angels rising to heaven, but the highest angel has fallen to the ground. He reads this FALLEN ANGEL as a reference to Icarus. Earlier, the game makes a reference to a group of CIA agents known as "Gray Fox", which Keogh claims is a "blatant nod" to the character of the same name in the Metal Gear Solid series. Grey Fox was a (real) code name for a CIA intelligence gathering group. Grey Fox, in Metal Gear Solid, is a cyborg ninja.
Throughout reading Killing is Harmless, I found myself asking the question, "what makes Brendan Keogh qualified to write a critical reading of this game?". Keogh claims that Spec Ops: The Line is a game that seeks to ask questions rather than answer them. Perhaps Killing is Harmless is the same way.