In Why We Fight, Mike Martin draws on his experience as a military veteran, biologist, and war studies academic to explore the root causes of human conflict and war. In short, Martin’s central argument is that humans fight for status and belonging. These two motivations are not necessarily conscious but rather subconscious drives shaped over millions of years of human evolution. While Why We Fight provides a cogent and powerful biological theoretical framework for understanding human conflict, the real aim of the book, I believe, is sociological. Martin sets out to convince the reader that our current dominant sociocultural explanations of human conflict are causing more problems than they solve and that a biologically informed view is necessary to prevent and combat political violence in all its forms.
The book is organized in 12 chapters that reflect a variety of interrelated topics, although there are two overarching themes: biology and culture. Martin first covers the biological side of his argument—the underlying psychological drives that subconsciously motivate us to use violence. Employing an evolutionary psychology framework, Martin explains how the process of evolution by natural selection has shaped the human mind over millions of years, endowing us with certain behaviors that, on average, increase our reproductive fitness.
In particular, Martin argues that group living and high social status allowed ancient humans a plethora of evolutionary benefits. Those who were mainly motivated by a desire for belonging and status were more likely to survive and reproduce and leave genes for these instincts in the gene pool. Over time, then, humans evolved corresponding neurobiological mechanisms driving these two motivations. Belonging is regulated by oxytocin, which motivates us to seek and find comfort in the security of groups. Status seeking is regulated by testosterone, which encourages us to climb the hierarchy within those groups, especially in response to challenges to our status, and more so in males than females. But Martin stresses that the causal effects of these two motivations are probabilistic, not deterministic. They only give us a “push” toward using violence in response to specific environmental stimuli.
After laying out the biological foundations of why we fight, Martin moves on to the sociocultural explanations. There is, according to Martin, a fundamental dilemma with group living. Every individual wants to reap the benefits of group living while simultaneously maximizing their selfish interests. If individuals feel that the benefits of the group are not worth the costs, they will splinter off and form their own groups. Martin posits that to solve this dilemma and maintain a cohesive social group, humans need to address the five interrelated problems of identity, hierarchy, trade, disease, and punishment. Over time, our solution to these five problems has been to socially construct various moral codes, religions, and ideologies. But here, Martin makes a bold claim: these social constructions only provide us with an illusion that we are making conscious and socially acceptable decisions, when we are actually making selfish, subconscious decisions to achieve belonging and attain status.
An example that Martin tackles repeatedly throughout the book is suicide terrorism. Martin’s confrontation with this form of terrorism is essential because it might appear to contradict an evolutionary perspective. After all, if war and violence came about as a result of evolutionary fitness, why would young and often childless individuals commit suicide for their group? Martin argues, quite convincingly, that suicide bombers are one of the more extreme examples of individuals desperately seeking a sense of belonging and status. Martin suggests that aggressive counterterrorism policies further alienate and humiliate these individuals, driving them to commit to an ultimate and desperate act to regain their lost sense of belonging and status. Furthermore, contrary to current counterterrorism doctrine, Martin argues that ideology is merely an illusion that facilities this behavior by making it socially acceptable and high status for those willing to make the ultimate sacrifice for their group.
A notable strength of this book is how Martin precedes each chapter with his own experiences in Afghanistan and elsewhere as a military officer. This allows the reader to situate Martin’s theoretical argument within a real-world example that is quite personal to the author and makes the academic sections more accessible. Perhaps the greatest strength of this book, though, is the real-world solutions that Martin offers. Martin’s perspective here follows other insurgency theorists who see extremism as primarily a result of social exclusion and alienation, which fringe groups pursuing new members eagerly seek to remedy (e.g., Mackinlay, Reference Mackinlay2009). Martin’s advice, then, is for governments to flip current counterextremism efforts on their head. The current doctrine of aggressively attacking these groups and their ideas results in the opposite of the desired effect—extremists become further alienated from wider society and more entrenched in their ideological group, not less. Thus, if governments want to combat extremism effectively, Martin argues they should instead foster a sense of inclusion through a shared ideology rather than exclusion through stigmatizing and criminalizing entire communities.
There are, however, several minor problems in the book. One such issue is that Martin relies on adaptationist logic as the foundation for the proximate cognitive mechanisms influencing our desire to fight. Unfortunately, these adaptationist claims—behavior X evolved in the past because of selection pressure Y—are often presented as fact when it is unclear whether they are empirically supported. For instance, Martin claims that human sexual dimorphism evolved because “male size is selected for ability to fight” (p. 68). While this is certainly logical, it may not necessarily be the case, as male size could have been selected for various reasons during human evolution. Hunting, for instance, is likely the reason why we evolved several physiological adaptations, such as sweat glands, and given the ubiquity of male hunting in hunter-gatherer communities, this may be a better explanation for the evolution of human sexual dimorphism (Apicella, Reference Apicella2014).
Besides anatomical adaptations, Martin also makes several ambitious claims that some of our psychological behaviors are products of natural selection. In one such passage, Martin argues that our “ancestors were more likely to die through losing group membership as a result of failing to participate as followers in war than through risking themselves in combat” (p. 89). How exactly do we know this was the case before the written record? Again, this is theoretically logical, but our groupishness tendency could have evolved for many reasons, or even as an exaptation—traits initially evolved for a different purpose. These adaptationist claims are also framed within the use of “modules” to explain how certain evolved behaviors exist in the brain. Yet, modularity in the evolutionary psychological sense is often misunderstood and heavily criticized, even by evolutionary psychologists (Pietraszewski & Wertz, Reference Pietraszewski and Wertz2021). The central problem here is that, throughout Martin’s book, these modules are just assumed to have been evolutionary adaptations without strong supporting evidence. For example, Martin claims that “the strong and obvious benefit to group living led to the evolution of a mechanism, a groupishness module” (p. 88), yet he provides no neurological evidence that this module exists or that it directly evolved as an adaptation to group living.
Despite these criticisms, Why We Fight has far more strengths than weaknesses. Even if one rejects adaptationist logic and modularity, Martin’s theory is well supported by a plethora of observational evidence in the cognitive and psychological sciences that is not susceptible to the same causal problems. Martin also repeatedly offers a wide variety of historical examples to repeatedly back up and solidify his theoretical arguments. Those in academia, especially undergrads interested in the root causes of human behavior and political violence, will find an easy and thought-provoking read. Why We Fight is also an especially important book sociologically. Martin’s solutions for counterextremism are well argued and novel, and they have important implications. As such, Why We Fight is an essential book for those whose understanding of human conflict has real-world consequences, such as military officers, counterterrorism officials, and government figures.
