Even the most cursory examination of the problem of amicicide in modern warfare is sufficient to suggest some conclusions regarding the causes, effects, and prevention of incidents in war involving the engagement of one friendly military force by another. We have examined in greater or lesser detail some 269 amicicide incidents of all types. Most were drawn from the record of the US Army in World War II, the last full-scale, global, high technology war to be fought. A few incidents of more recent occurrence have been identified and described from the personal recollections of participants in the Vietnam conflict. This study, limited though it has been by the time available for its preparation and the inadequacies of the available evidence, nevertheless permits some tentative conclusions to be drawn, and each incident, standing by itself, provides some insight into the problem of amicicide.

The incidents examined in this study suggest that in the past, incidents involving friendly aircraft mistakenly engaging friendly ground forces were, by a small margin, the most frequent type (99 out of 269 incidents, or roughly 37 percent). Attacks by friendly artillery on friendly ground forces were almost as common (98 out of 269 incidents, or roughly 36 percent). The engagement of friendly aircraft by friendly antiaircraft weapons proved to be a relatively minor problem (only 15 out of 269 incidents, or about 5 percent). A fair number of incidents involved the direct engagement of friendly ground troops by other friendly ground troops (58 out of 269, or 22 percent).

Of the latter category, only three incidents were seen to involve the mistaken engagement of friendly tanks by other friendly tanks or antitank weapons. Given the obvious weaknesses of the sample, these proportions cannot be viewed as anything more than a rough approximation of the order of magnitude. They can, however, perhaps suggest the priority of efforts to reduce amicicide incidents.

The number of casualties in past wars attributable to friendly fire is impossible to determine with any accuracy from the available data. Our sample of 269 incidents involved a total of nearly 4,000 friendly casualties, with most incidents (81) involving fewer than 5 casualties per incident.

It appears that amicicide incidents account for something less than 2 percent of all casualties in battle. American casualties in the Second World War were about 774,000. If 2 percent is a reasonably accurate estimate of the total casualties attributable to amicicide, then about 15,480 Americans, or the equivalent of one full infantry division, fell victim to friendly fires in World War II. Similarly, out of 57,000 US casualties in Vietnam more than 1,100 could thus be counted as victims of amicicide.

Whether the loss, permanent or temporary, of 2 percent of the nationis military manpower in a given conflict is significant and thus demands an extraordinary application of resources to avoid is a question that must be answered at the highest policy levels. It should be noted, however, that the impact of amicicide on combat power is geometric, not linear. Each amicicide incident that results in friendly troops killed or wounded has an adverse effect on morale and confidence in supporting arms, disrupts the continuity of friendly operations, and represents one bomb, shell, or bullet that should have fallen on the enemy to reduce his combat power rather than our own.

In terms of the number of casualties produced, air amicicide incidents clearly predominate as the most destructive, both in total and per incident. [1]

Artillery incidents are nearly as destructive in the aggregate but usually involve only small numbers of casualties per incident. [2]

Although frequent, ground incidents are not often heavy casualty producers, even though they can significantly disrupt the flow of combat operations. [3]

Antiaircraft amicicide is perhaps the least significant type, resulting only in rare incidents in more than a few casualties per incident. [4]

Again, the relative priority for investigation and application of resources for prevention is suggested; that is, we would do well to concentrate our efforts on understanding and trying to prevent air and artillery amicicide first.

Some contributory factors were found in this brief study to be relatively insignificant. For example, the type of combat operation in progress when an amicicide incident occurred had little or no bearing on the occurrence. While it may be seen from the narrative that amicicide incidents were slightly more frequent during withdrawals and patrol actions, the pattern generally conforms to the dominant type of tactical operation in each conflict.

Visibility plays a role in some types of amicicide incidents and not in others. In cases of air and ground amicicide there appears to be a relatively high correlation between reduced visibility (night, fog, smoke) and the occurrence of incidents. On the other hand, visibility was apparently not a significant factor in cases of artillery or antiaircraft amicicide.

The evidence examined in this study points clearly to one factor as the primary cause of most amicicide incidents: direct human error.

Only rarely were such incidents due to mechanical failure, but in innumerable cases the incident resulted from some identifiable human failure. The nervousness of green troops, a lack of control or of fire discipline imposed by calm and decisive leaders, the lack of adequate coordination of operations by commanders and staff officers, and disorientation, confusion, and carelessness of pilots, gunners, or crewmen were the predominant causes of most incidents.

Fear and the fog of battle have conspired to produce the amicicide incidents described in this study. Surprisingly few incidents can be traced to a genuine misidentification of friendly for enemy troops. Almost always a lack of coordination or some more direct human error was responsible for the engagement of friendly forces by their supporting air, ground, or artillery weapons.

Sometimes incidents resulted from human failures as simple as the inadvertent pushing of a button at the wrong time, the transposition of a series of numbers, or a mistake in arithmetic. On other occasions, the human failure was more complex in its origins, and commonly the fear and confusion so prevalent on the battlefield played a major role. As the author of a report on friendly fire casualties in Vietnam noted, "They [amicicide incidents] also serve as a reminder that the battlefield is and always has been a strict and harsh disciplinarian. Those who have deviated from proven techniques, used "short cuts" because it was the "easy way out" or failed to follow directives and established rocedures, have done so with disastrous results." [5]

Although the causes of amicicide incidents may be uncertain and hidden in the complex functioning of the human mind, the effects of such incidents are much more certain and patent. The first and most obvious effect is the unnecessary death and suffering of soldiers due to the actions of those dedicated to their support. Standing alone, the avoidance of such occurrences is a worthy goal. But amicicide also has a more subtle but very important impact on the overall conduct of military operations.

In general, the occurrence of even the most serious amicicide incidents seems to have had only a local and transient effect on the outcome of combat operations. Certainly, such incidents have delayed or even completely halted offensive operations, disrupted and weakened defensive operations, and, on occasion, precipitated withdrawal and local defeats. The negative impact of amicicide on friendly combat power is, however, often more complex and subtle.

Each incident contributes in some measure to the subtle degradation of combat power by lowering morale and confidence in supporting arms so necessary to the successful pursuance of modern combined arms operations. This effect is, as has been mentioned, geometric rather than linear.

As expressed in the MACV study of Vietnam amicicide, "The statistics and examples of incidents, although important, cannot and do not of themselves reveal the complete picture of the deplorable loss of life by fire from friendly sources. All service components are acutely aware of the seriousness of these incidents in terms of lowered effectiveness of the fighting forces, lessened rapport between US forces themselves and Vietnamese Nationals, and the unquestionable adverse effect on the overall military effort." [6]

The solutions and preventive measures required to reduce or eliminate incidents of amicicide on future battlefields are problematic. Given the clear preponderance of direct human error as the source of most amicicide incidents, it is manifest that preventive measures must be directed toward the correction or improvement of human frailties, and these, as always, are the factors least amenable to correction. The fear and confusion of the battlefield cannot be eliminated. Indeed they are likely to be even more prevalent on the battlefield of the future than they were on the battlefields of the past.

The combat experience and steadiness born of the soldier's confidence in his cause, his weapons, his comrades, and himself can be gained in the end nowhere but on the field of battle itself. A vigorous study of past experience and the careful selection and rigorous training of soldiers under conditions closely approximating those of actual combat may prove of some value in reducing the incidence of amicicide, but in the last analysis the only truly effective solution is experience coupled with an unremitting attention to detail.

Obviously, we cannot hope to eliminate amicicide as a problem in modern war, but direct and forceful attention to its human causes may bring some reduction of its incidence and effect.

Modern people, and especially Americans, have increasingly sought to overcome their most difficult problems, particularly military problems, by the application of science and technology.

While advanced technological devices may certainly be of significant value in reducing amicicide by better location and identification of friendly troops and equipment and by improved communication and coordination, they cannot provide a total solution to what is essentially a problem of human frailty.

Indeed, there is every reason to suspect that the advance of military technology has increased rather than reduced the problem of amicicide. As the use of technologically sophisticated weapons systems has increased, the limits of human ability to control such destructive forces have been approached. With respect to the problem of amicicide it may be suggested that the optimum point of matching the capabilities of men and machines may already have been passed and that the gap between the capabilities of machines and the human ability to control them adequately is increasing.

The implications of this gap for amicicide in future war are clear: amicicide may be a greater problem on the future battlefield than ever before, both in terms of frequency and the number of casualties produced thereby.

The effective application of better selection and training or of modern technology to solve the problem of amicicide is dependent upon the degree to which amicicide is viewed as a problem of significant seriousness warranting the expenditures of resources to reduce its occurrence and the proper selection of areas in which such resources may be fruitfully employed. The conclusions suggested by this study are that the human factors responsible for the occurrence of amicicide incidents of all types should receive priority.

Regardless of the resources applied, the problem of amicicide cannot be eliminated by any means in the foreseeable future. Today, as in earlier times, the best intentions and efforts are insufficient to prevent the occurrence of amicicide, which remains a problem for all military forces right up to the present, as suggested by an article that appeared in the Kansas City Times on Wednesday, 2 January 1980: "Confusion, fear and gunfire in the pre-dawn darkness of an ambush site produced Northern Ireland's first casualties of the decade Tuesday--a British squad leader and a private, killed by their own men." [7]