book review responses

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MSCJ 550 ADE – Book 1 Review: On Killing

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MSCJ 550 ADE – Book 1 Review: On Killing

On Killing: The Psychological Cost of Learning to Kill in War and Society

Abstract

This review examines On Killing: The Psychological Cost of Learning to Kill in War and Society by Lt. Col. Dave Grossman (1996/2009). The book explores the psychological processes involved in killing, the conditioning methods used by military and law enforcement institutions, and the emotional and physiological consequences of lethal force. This analysis summarizes the book’s major themes, evaluates its scholarly strengths and limitations, and discusses its relevance to criminal justice literature. The review concludes that while Grossman’s work is influential and insightful, some methodological weaknesses require cautious interpretation.

Lt. Col. Dave Grossman’s On Killing (1996/2009) remains a foundational text in the study of combat psychology and the human response to lethal force. Grossman, a former Army Ranger and psychology instructor at West Point, argues that most humans possess an innate resistance to killing, and that modern institutions have developed conditioning techniques to overcome this resistance. The book blends historical analysis, psychological theory, and firsthand accounts to explore how individuals learn to kill, how they respond during lethal encounters, and how they cope with the aftermath. This review summarizes Grossman’s key arguments, critically evaluates his methodology and use of sources, and assesses the book’s contribution to criminal justice scholarship.

Grossman’s central thesis is that humans are naturally reluctant to kill members of their own species. Drawing on military records, interviews, and psychological research, he argues that prior to World War II, most soldiers intentionally avoided firing directly at the enemy. According to Grossman, the U.S. military responded by adopting conditioning techniques—rooted in behaviorist psychology—to increase firing rates and combat effectiveness. These methods include realistic training, desensitization, and reflexive firing drills designed to bypass conscious resistance.

The book also examines the psychological and physiological effects of lethal force. Grossman describes the stages of arousal under stress, including perceptual distortions, auditory exclusion, and time dilation. He further explores the emotional aftermath of killing, emphasizing the prevalence of guilt, trauma, and post‑traumatic stress reactions. In the revised 2009 edition, Grossman expands his analysis to include contemporary warfare, law enforcement shootings, and the potential influence of violent media on civilian aggression.

One of the strengths of On Killing is its accessibility. Grossman presents complex psychological concepts in a clear and engaging manner, making the book valuable to both academic and practitioner audiences. His discussion of stress responses and post‑shooting trauma aligns with modern research on officer‑involved shootings, and his emphasis on realistic training parallels current law enforcement practices such as scenario‑based instruction and stress inoculation. In this sense, Grossman’s work anticipated many reforms that have since become standard in policing.

However, the book is not without limitations. Critics have noted that Grossman relies heavily on anecdotal evidence, personal interviews, and secondary sources rather than systematic empirical research. Some of his claims—particularly those regarding firing rates in earlier wars—have been challenged by historians who argue that the data may be overstated or based on flawed methodology. Additionally, Grossman’s assertions about violent media and video games have been contested by more recent studies showing inconsistent or minimal links between media exposure and real‑world violence. These methodological concerns suggest that while Grossman’s insights are valuable, some conclusions should be interpreted with caution.

Grossman’s background as a military officer contributes both credibility and potential bias. His firsthand experience lends authority to his discussion of combat psychology, but it may also influence his interpretation of data or lead to generalizations that extend beyond the available evidence. At times, the book blends empirical analysis with moral commentary, which can blur the distinction between scientific observation and personal conviction.

Despite these limitations, On Killing makes a meaningful contribution to criminal justice literature. The book provides critical insight into the psychological realities of lethal force—an area of increasing importance in policing. Understanding stress responses, decision‑making under pressure, and the emotional toll of deadly encounters is essential for developing effective training, officer wellness programs, and use‑of‑force policies. Grossman’s work also raises ethical questions about conditioning individuals to use force, prompting reflection on how training methods shape officer behavior and community interactions.

In conclusion, On Killing is a significant and thought‑provoking work that offers a unique perspective on the psychology of lethal force. While some methodological weaknesses limit the generalizability of certain claims, the book remains influential in both military and law enforcement contexts. Its exploration of stress, trauma, and the moral dimensions of violence continues to inform discussions of police training, officer wellness, and use‑of‑force policy. Grossman’s work encourages readers to consider not only how individuals are trained to kill, but also how society supports those who bear the burden of doing so.

References

Grossman, D. (2009). On killing: The psychological cost of learning to kill in war and society. Back Bay Books. (Original work published 1996)