John Pettegrew's Light It Up examines what he calls the “optics” of combat in the twenty-first century, by which he means the growing importance of the eye, both literal and figurative (as in “mind's eye”), in the execution of postmodern warfare. Drawing on a wealth of primary source material – from the oral histories and memoirs of Marine Corps veterans to Marine Corps training manuals, policy statements, and recruitment materials – Pettegrew elucidates the corps's institutional “outlook” on war and killing and takes heed of the allures of combat even as he critiques the war in Iraq.

Following in the footsteps of French cultural theorist Paul Virilio (Speed and Politics (2006; first published 1977) War and Cinema: The Logistics of Perception (1989; first published 1984) and The Information Bomb (2005; first published 1998)), Light It Up examines the relationship between war, technological innovation – especially technologies of seeing and perception – and human history. Whereas Virilio assumes that the rise of the machine entails the descent of man, however, Pettegrew depicts the marriage of man and machine as a complex and still relatively unpredictable process. In essence, he wants to know how war has become automated for the soldiers who engage in it so that he might better understand why it has become so automatic a response to political and social problems in the twenty-first century. The aim is as much to disrupt as to lament these developments.

The introduction and first three chapters of the book show how seeing and targeting have become synonymous within the US Marine Corps. Asserting that “‘the Marine eye for battle’ is a historical enterprise” (8), Pettegrew traces the rise of “stimulus-response and see–shoot infantry training” (4) to the World War II infantryman's reluctance to fire on the enemy. To counteract this reluctance, the corps created a system of rehearsal and visualization exercises designed to automate the infantryman's reaction to battlefield stimuli. Chapters 2 and 3 examine the broader cultural construction of the warrior mindset via the production and consumption of “war porn” (both Hollywood war films and YouTube combat videos) and violent video games. In combination, Pettegrew argues, the training exercises, films, videos, and games habituate would-be Marines to the idea of killing by reducing enemy soldiers to mere “targets” and rewarding those who shoot best and without thinking: “Procedural memory is the goal” (90).

Chapter 1 places this training regimen in the context of the larger, optically based doctrines of network-centric and maneuver warfare. The former entails using advanced technology to achieve “superior sight and perception” (14) on the battlefield while the latter involves “blinding” the enemy through shock and awe. Pettegrew introduces the various new technologies and tactics deployed in Iraq to secure rapid dominance and then reckons honestly with the results. The overreliance on technology turned the Marines into an unprecedentedly lethal killing force, he notes, but it also undermined the long-term viability of the operation by preserving US life at the expense of Iraqi civilians and allies (not to mention the mental health of the soldiers trained so well to pull those triggers).

The final three chapters of the book consider the transformations wrought by the embrace of counterinsurgency doctrine and speculate on the future trajectory of the Marine Corps's “optically calibrated, battle-ready mindset” (1). What happens when Marines are told, for example, to “turn off the kill switch” and make nice with the locals? How will the corps's embrace of rescue and relief missions abroad affect its battle-readiness (not to mention the definition of humanitarianism)? How will the integration of women affect the fighting force? And what does the move toward fully automated warfare (the use of drones, robots, and mecha-suits) portend for humanity?

Overall, I find Pettegrew's questions intriguing, but his answers a little less satisfying. In part, this is a failure to place the evidence in perspective. In the chapter on war porn, for example, he fails to grapple with the selective and anecdotal nature of the YouTube commentaries used to support his hand-wringing assessment of these soldier videos. A few hundred bloodthirsty yahoos engaged in a highly structured form of rhetorical combat hardly constitutes a representative sampling of US opinion. He also occasionally claims there is something new about the relation between optics and killing as deployed in Iraq; it constitutes a “generational difference” and a uniquely “synthetic” mode of seeing (155). This assertion not only mischaracterizes transformations that have been under way since the nineteenth century; it also reduces the book's more complicated argument about the historical and cultural construction of battlefield optics to a form of technological determinism (à la Virilio). Light It Up is strongest when it depicts the relationship between battlefield conduct and technologies of perception as a “tightening cultural loop” (165), or process that is both ongoing and indeterminate. What distinguishes this book from Virilio's seductive but ultimately despairing accounts of technologically mediated warfare is its attention to the humans behind, inside, and in the crosshairs of the war machine. For Pettegrew, war is still a hybrid enterprise, and humans remain at least potential ghosts in the machine. How best to awaken that potential is the only question.