Science and technology have always been decisive factors in war. Archers were capable of killing more effectively than warriors armed with spears. Armies equipped with repeating rifles claimed a distinct advantage over those armed with muskets. The United States’ ability to produce the atomic bomb led to the surrender of Japan at the conclusion of World War II. It is obvious, in other words, that science, technology, engineering, and math have an important role to play in guiding the evolution of national militaries. What may be less obvious is that advances in psychology may have an even more important role to play, particularly in the types of conflicts increasingly common in the twenty-first century.

There are several reasons this is the case. The major wars of the twentieth century involved full-intensity conflict between nations, with success often measured by territory gained or lost. Countries that could exploit advances in chemistry to produce more lethal explosives or leverage the science of physics to engineer faster and more maneuverable airplanes stood a better chance of defeating the enemy. These applications of science and technology had a direct impact on definable military objectives.

Contrast this with the wars of the twenty-first century. In the United States' most recent conflicts, the primary adversary hasn't been other countries but, rather, ideologically motivated coalitions of fighters determined to achieve their political goals with unconventional tactics, including suicide attacks and remote bombings. Currently, ISIS provides a case in point. In asymmetric warfare of this sort, it is hard to determine and locate the perpetrators of an attack.

Under these conditions, powerful, state-of-the-art military weapons systems have very limited utility. Unlike World War II, when Allied air forces bombed factories and other military targets in Germany to degrade their ability to wage war, such clearly defined targets are often lacking in contemporary military operations. In the absence of clear targets, strategic air and missile systems are limited in impact and value. Highly lethal but indiscriminate weapons may result in greater strategic harm than in operational military effect, something the Israelis experienced in the recent conflict in the Gaza Strip. In short, the large-scale kinetic weapons that the military uses to deter or potentially fight peer adversaries are largely irrelevant to conflicts of this type.

Fortunately, the U.S. military can adapt to this new type of warfare. The first step will be to understand that terrorist organizations and other insurgent groups rely primarily on psychological manipulation to achieve their goals. For example, the material impact of the 9/11 attacks pales in comparison to the psychological damage: the fear and uncertainty that the attacks created still affect how the U.S. public thinks about national security.

The United States military must learn to develop psychological tactics of its own to counteract these psychological threats. For example, with sufficient psychological training, troops using the latest command, control, and intelligence systems would have enormous potential advantages over their adversaries. These systems, which monitor friendly and enemy activity in near-real time, should allow troops to organize quicker and more precise military responses to threats. But they can do so only if they first learn how to perceive, understand, and utilize the vast amounts of information that these technologies make available. Cognitive psychologists will thus play a central role in developing next-generation command and control technologies, and also in developing training strategies to enable operators to exploit the full capabilities of these systems.

The military would also benefit from paying more attention to the emotional damage inflicted on its troops. Thirteen years of continuous war has placed an enormous psychological burden on the country's relatively small, all-volunteer force. Many members of the military have been sent multiple times to combat areas, with little time for recovery between deployments. Suicide rates of active duty military and veterans have skyrocketed since 2001, and the military and veteran health care systems are overloaded with patients suffering from combat-related psychological disorders, including post-traumatic stress disorder and depression. Many experts estimate that 15 percent of the military qualify as “psychologically wounded.” An even greater number than that have emotional problems that interfere with their day-to-day effectiveness in the military. That is to say, of the U.S. Army’s 500,000 soldiers, 75,000 or more may be psychologically impaired to an extent that compromises their combat effectiveness.

In that sense, the military must focus more on psychological care to maintain the combat strength of the military, both by treating combat stress disorders and training soldiers to avoid these injuries through developing better personal resilience skills. The latter approach—exemplified in the Army’s Comprehensive Soldier Fitness program—may prove more important in the long run. Preventing psychopathology is far preferable to having to treat it. A soldier who is psychologically damaged is apt to lose his ability and will to fight; a volunteer force like the United States Army simply can’t afford the risk of having large numbers of psychologically afflicted troops.

The military should also begin using psychology to inform its selection and training of leadership. Psychological competence, social intelligence, and an ability to think quickly and adaptively should be treated as necessary qualifications for officers and other military leaders. The military should also draw on new findings in the scientific study of in extremis leadership to train a generation of military leaders capable of building cohesive and resilient combat teams. Social and organizational psychologists already have the knowledge to inform the military on how to select and develop such leaders. Psychologists can help train leaders how to think adaptively, how to be mentally agile, and how to inspire and motivate others under conditions of high threat.

Raw kinetic power is and always will be critical to military success. In face-to-face encounters, armies with more powerful weapons will usually prevail, at least in a discrete engagement. But as the United States learned in Iraq in 2003, and continues to experience in Afghanistan, the cessation of major combat operations is often followed by a long period of asymmetric war, in which success can not be achieved through traditional combat. In this new phase of warfare, psychology’s core competencies of understanding individual and group behavior—of both the enemy and one's own forces—then become the key to success.

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  • MICHAEL D. MATTHEWS is Professor of Engineering Psychology at the United States Military Academy and author of Head Strong: How Psychology Is Revolutionizing War (Oxford University Press, 2014). He is currently on sabbatical from West Point, serving as a Fellow with the Army Chief of Staff’s Strategic Studies Group. The views expressed herein are those of the author and do not reflect the position of the United States Military Academy, the Department of the Army, or the Department of Defense.
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