Human Factors In Warfare: Suppression

Images from a Finnish Army artillery salvo fired by towed 130mm howitzers during an exercise in 2013. [Puolustusvoimat – Försvarsmakten – The Finnish Defence Forces/YouTube]
[This piece was originally posted on 24 August 2017.]

According to Trevor Dupuy, “Suppression is perhaps the most obvious and most extensive manifestation of the impact of fear on the battlefield.” As he detailed in Understanding War: History and Theory of Combat (1987),

There is probably no obscurity of combat requiring clarification and understanding more urgently than that of suppression… Suppression usually is defined as the effect of fire (primarily artillery fire) upon the behavior of hostile personnel, reducing, limiting, or inhibiting their performance of combat duties. Suppression lasts as long as the fires continue and for some brief, indeterminate period thereafter. Suppression is the most important effect of artillery fire, contributing directly to the ability of the supported maneuver units to accomplish their missions while preventing the enemy units from accomplishing theirs. (p. 251)

Official US Army field artillery doctrine makes a distinction between “suppression” and “neutralization.” Suppression is defined to be instantaneous and fleeting; neutralization, while also temporary, is relatively longer-lasting. Neutralization, the doctrine says, results when suppressive effects are so severe and long-lasting that a target is put out of action for a period of time after the suppressive fire is halted. Neutralization combines the psychological effects of suppressive gunfire with a certain amount of damage. The general concept of neutralization, as distinct from the more fleeting suppression, is a reasonable one. (p. 252)

Despite widespread acknowledgement of the existence of suppression and neutralization, the lack of interest in analyzing its effects was a source of professional frustration for Dupuy. As he commented in 1989,

The British did some interesting but inconclusive work on suppression in their battlefield operations research in World War II. In the United States I am aware of considerable talk about suppression, but very little accomplishment, over the past 20 years. In the light of the significance of suppression, our failure to come to grips with the issue is really quite disgraceful.

This lack of interest is curious, given that suppression and neutralization remain embedded in U.S. Army combat doctrine to this day. The current Army definitions are:

Suppression – In the context of the computed effects of field artillery fires, renders a target ineffective for a short period of time producing at least 3-percent casualties or materiel damage. [Army Doctrine Reference Publication (ADRP) 1-02, Terms and Military Symbols, December 2015, p. 1-87]

Neutralization – In the context of the computed effects of field artillery fires renders a target ineffective for a short period of time, producing 10-percent casualties or materiel damage. [ADRP 1-02, p. 1-65]

A particular source for Dupuy’s irritation was the fact that these definitions were likely empirically wrong. As he argued in Understanding War,

This is almost certainly the wrong way to approach quantification of neutralization. Not only is there no historical evidence that 10% casualties are enough to achieve this effect, there is no evidence that any level of losses is required to achieve the psycho-physiological effects of suppression or neutralization. Furthermore, the time period in which casualties are incurred is probably more important than any arbitrary percentage of loss, and the replacement of casualties and repair of damage are probably irrelevant. (p. 252)

Thirty years after Dupuy pointed this problem out, the construct remains enshrined in U.S. doctrine, unquestioned and unsubstantiated. Dupuy himself was convinced that suppression probably had little, if anything, to do with personnel loss rates.

I believe now that suppression is related to and probably a component of disruption caused by combat processes other than surprise, such as a communications failure. Further research may reveal, however, that suppression is a very distinct form of disruption that can be measured or estimated quite independently of disruption caused by any other phenomenon. (Understanding War, p. 251)

He had developed a hypothesis for measuring the effects of suppression, but was unable to interest anyone in the U.S. government or military in sponsoring a study on it. Suppression as a combat phenomenon remains only vaguely understood.

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Shawn Woodford
Shawn Woodford

Shawn Robert Woodford, Ph.D., is a military historian with nearly two decades of research, writing, and analytical experience on operations, strategy, and national security policy. His work has focused on special operations, unconventional and paramilitary warfare, counterinsurgency, counterterrorism, naval history, quantitative historical analysis, nineteenth and twentieth century military history, and the history of nuclear weapon development. He has a strong research interest in the relationship between politics and strategy in warfare and the epistemology of wargaming and combat modeling.

All views expressed here are his and do not reflect those of any other private or public organization or entity.

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  1. I think this is a very interesting topic for those of us engaged in the development of quantitative models of battlefield behaviour.

    At the end of the article you write “He had developed a hypothesis for measuring the effects of suppression “. I may have missed it but I could not see a clear statement of what this hypothesis was. As Dupuy had a good intuitive feel for what the issue may be in many of these matters, it could be a valuable pointer to the answer. Would you state it for me?

  2. Clinton,

    From about 1993-1996 we did have a series of contracts on Suppression. Some of it was in coordination with UK researchers and the major contract was a teaming agreement with another contractor with them as the lead. The lead contractor never completed the final report, stiffing the U.S. government, and stiffing us for $30K. It was an embarrassing and shameful effort on their part. Their owner drank himself into the hospital, they went out of business, and never fulfilled their contract.

    I will pull up our old files and post something up on the blog over the next week or two. Right now I am editing the manuscript for my next book, so that has to take priority.

  3. IMHO the breakpoint for creating Suppression in an infantry unit in modern warfare is about the same as that in the Napoleonic period and earlier for a unit beginning to become shaken, falter and fail to move forward.

    Neutralisation is more severe and would be about the point at which the unit same unit in the 19th Century or earlier routs.

    There seems to be a point at which firepower becomes more accurate at a longer range and it is no longer sensible for an infantry man to run. They go prone instead. In the Napoleonic era and earlier if an infantryman runs he can get clear of the danger zone in a few seconds. Not so once rifled muskets with the Minnie bullet are common on the battlefield and the lethal range goes over about 300 meters..

    That is my hypothesis, but I am not sure how to test it.

  4. The British OR Group #2, working in the ETO did two studies on suppression in 1944-45. That is kind of the starting point of the discussion. They were the first, and to date, the most extensive, studies done on the subject. They actually produced figures of how many rounds an hour it takes to suppress infantry.

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