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Combat Effectiveness

Combat Effectiveness. The mystery of why men fight has always tantalized students of warfare. Explanations usually reflect cultural and military‐institutional prejudices. Men have fought—and died—against all instincts for survival because of many factors: tribal loyalties, charismatic leaders, ethnic and cultural characteristics, strict military discipline, demanding training, superior physical condition, hatred and revenge, advanced weapons, love of God or gods, belief in an afterlife that favors slain warriors, fate, sexual and biological imperatives, loot, and national patriotism. Not until the nineteenth century did military commanders and planners begin to study the phenomenon, assisted in the last 100 years by social scientists and psychologists. Despite a brief confidence that unit cohesion and peer pressure determined combat performance, the question of combat motivation remains elusive, subject to the interaction of many characteristics of military units and the conditions of particular types of warfare.

Combat effectiveness should be seen, first, as only a part of a general framework of military effectiveness. National defense politics produces the resources for the armed forces: leadership, manpower (and now womanpower) in quality and quantity, advanced weapons, logistical support, public support, a sense of legitimacy and purpose, and a promise of rewards and compensation for the service member and his or her immediate family, especially as dependent survivors of dead or permanently incapacitated veterans. Political effectiveness is not within the province of the armed forces—except in a military dictatorship—but it certainly can be affected by how well or poorly resources are transformed into capable military forces by the nation's military leadership. Linked to political effectiveness is strategic effectiveness, or the general framework for the employment of military forces in the pursuit of war aims or the deterrence of war. Sound strategy always considers the relationship of means to ends, and the issues of appropriateness and proportionality, when examining the use of real or threatened violence as a political instrument. The history of warfare is strewn with examples in which flawed strategy doomed combat‐effective forces to eventual defeat, the most recent being the experience of Germany and Japan in World War II.

Combat effectiveness is a combination of operational and tactical effectiveness, which is the performance of military units in direct contact with the enemy. Questions of operational effectiveness usually focus on the integration of forces of different combat specializations (land, air, sea) and nationality (allies); logistical sustainability for a campaign extended in time and/or distance; provisions for effective higher command in both the personal and the technical sense; the identification of fundamental enemy weaknesses; and the maximum combination of overwhelming firepower and surprising maneuver. Tactical effectiveness concentrates on the actual performance of combatant forces (infantry, armor, artillery, warships, combat aviation units) in engagements with the enemy. Operational and tactical effectiveness have an organic relationship; neither in isolation is likely to bring battlefield victory. For example, a sound operational concept like the attack by U.S. Navy submarines on Japanese commerce (1942–1945) can be ruined (it wasn’t) by poor submarine employment, faulty torpedoes, and timorous officers and crews—all tactical considerations.

The American experience in identifying fundamental truths about combat effectiveness and transforming theory into training practice has undergone substantial change since the creation of the U.S. armed forces. It has also varied by service, since the army and Marine Corps have always worried about the special trials of ground combat, while the air force (and its predecessors) and the navy have argued that their combat functions have unique characteristics that differentiate them from ground combat units. Until the twentieth century, the normative questions about combat effectiveness concentrated on training, discipline, and mental conditioning. For wartime ground forces, the issue became avoiding the fatal combination of untrained volunteer officers with untrained militia and volunteers. Lack of peacetime military training for citizens meant that few emergency units could fight Indian warriors, European troops (i.e., the British), or even each other (the Civil War) with any prospect of success with acceptable casualties. In fact, the citizen‐soldier showed that he could fight well—if properly led and deployed in the tactical defense. Citizen‐officers, on the other hand, showed little understanding of the demands of command until they had been awakened by losing a battle or two. In the early twentieth century, the problem of officership in wartime armies was addressed by providing peacetime training for prospective officers in special summer camps and at land‐grant universities, and after 1916 in the Reserve Officers' Training Corps (ROTC).

The U.S. Navy viewed its combat efficiency problems differently since its peacetime maritime constabulary missions provided it with at least a cadre of trained mariners around which to build wartime naval forces. As long as the United States had a large merchant marine—a condition that lasted into the second half of the nineteenth century—the navy could draw merchant seamen and officers into uniform for wartime service in adequate numbers and skills. The Union navy of the Civil War represented the high point of this policy. Merchant seamen might need additional training in gunnery, but they already knew discipline and seamanship from their civilian occupations. Only when the navy had to depend upon landsmen for recruits did it worry about recruit and advanced training; most officers came from the Naval Academy and needed little more than practical experience to function well. For the navy, the major challenge became training all its personnel in the technological advances that eliminated sails and muzzle‐loaded broadside guns late in the nineteenth century. New demands came from steam engines, fire direction systems, advanced turret ordnance, torpedoes, and (eventually) radar‐defined and then electronic naval combat effectiveness; the introduction of aircraft and submarines only accelerated the concern for technical competence as the foundation of combat performance.

The entry of aircraft as weapons over land and sea created another approach to combat effectiveness that combined technical training with elite personnel selection—a common approach in the armies and navies of all the belligerents in World War I, and continued by separate or integrated air forces thereafter. The U.S. Army Air Service determined that the requirements of technical training, hurried under wartime conditions, meant that it had to recruit young men of bold temperament, exceptional physical skill and conditioning, and the highest intellectual acuity, with an emphasis on academic performance in formal schooling. This argument that air combat demanded the best human potential was extended to all other aircrews and even to ground service personnel. Pilots, who would almost always be officers, were promised extra pay, symbols of skill (winged insignia) and daring, freedom from ordinary military discipline, exceptional living conditions, special medical attention, and organizational preference in matters of command and training. The public fascination with aviation, as well as potential employment in the civilian aviation industry, simply reinforced the cult of the pilot. The only real modification of his ethos has been the realization that flying skill does not perish with youth and that successful combat pilots are experienced in terms of hours flown, not chronological age or prime physical condition. The spiraling demands of aviation technology and the increase of multiperson aircrews—even for superior fighters like the F‐4 and F‐14—also reinforced the experience of World War II (high‐quality recruits still needed much flying to be combat effective). The cost of such flight training remains a concern, but the U.S. Air Force has substituted virtual reality simulator training with some success.

In the classic tradition, observers of human performance in combat from Ardant du Picq to S. L. A. Marshall have stressed the importance of group cohesion and collective values, but the issue is complicated and in a sense exaggerated in American experience by other factors. First, a ship's crew may or may not be happy, but its fate is certainly collective: stricken warships almost always produce superhuman, selfless behavior on the part of some crewmen. The issue there, however, is not killing the enemy but saving comrades. In combat, shipboard organization stresses teamwork and a social context of cooperation and trust, based on repetitive training. The U.S. Navy has used demanding psychological testing in selecting submariners since World War II, but the screening process emphasizes adjustment to claustrophobic living rather than combat performance. Physical ability is less important than steadiness under stress and keen technical skills, a condition that also applies to aircrew service. The navy and the air force also understand the effects of fatigue, poor health, sustained tension, mental exhaustion, and eating habits on effectiveness, and expend special effort to address these problems, which make them the envy of ground forces.

Since the nineteenth century, American ground forces had plenty of group cohesion—they fought or ran in groups—and the army did not worry about the problem until World War I, when conscription produced combat units that lacked such with civilian bonds as ethnic homogeneity, community identification, religious preference, common occupation, and self‐selected leadership. In the Civil War, volunteer infantry regiments like the 69th New York, the 1st Minnesota, the 15th New Jersey, the 20th Maine, the 4th Alabama, the 26th North Carolina, and the 27th Virginia needed no social scientist to tell them about the importance of group cohesion in combat. The introduction of conscription and the use of individual replacements by the army in every war since 1917 produced serious concern that the army would have to create group cohesiveness where none existed. The Marine Corps, never homogeneous, used one approach: complete institutional socialization from boot camp to battlefield. Smaller in number (the Marine Corps has never been larger than one‐fifth the size of the army), Marines found their inspiration in limited occupational specialization (“every Marine is a rifleman”) and dedication to the Corps, not some part of it. This organizational loyalty centers on the commitment to combat. The army, on the other hand, found that it had a special problem in keeping infantry units effective in wartime (America's enemies have consistently rated U.S. Army artillery and aviation as more fearsome than its foot soldiers). The issue emerged in the late stages of World War I when the divisions of the American Expeditionary Forces endured a lack of trained replacements, of effective junior leaders, of healthy troops untouched by bad weather and the flu epidemic, and of superior firepower. That experience reshaped army definitions of combat effectiveness in World War II and thereafter.

The ground forces in World War II showed weakness in almost every aspect of combat effectiveness, especially in infantry units from divisions to squads. Arguing that they required high‐quality personnel, the army air forces and navy took more than their fair share of the ablest men; the army ground forces made the wound self‐inflicted when they placed similar talent into support units in excessive numbers. Combat divisions received personnel on the basis of physical condition, not maturity and intelligence, and casualties quickly thinned the ranks of junior leaders. Elite units (airborne divisions, ranger battalions) enjoyed substantial training periods, as well as quality personnel; but the average infantry and armor division had little relief from combat, especially in the European theater. Divisions that entered combat in 1942 stayed in action until the end of the war; divisions committed in June 1944 never really had an opportunity thereafter to rest and retrain.

The army's own decision to cap the wartime ground forces at eighty‐nine divisions had much to do with the difficulty of maintaining combat effectiveness. This condition could not be remedied, even with the infusion of quality (but untrained) troops from service units late in 1944. Ground combat analysts also reported that excessive fatigue caused by overloading, poor weapons training, and a lack of good junior officers and NCOs reduced combat effectiveness. The relative aggressiveness and skill of German infantry suggested a new stress upon the factor of peer pressure, based on studies by sociologists Edward Shils and Morris Janowitz as well as the work on American soldiers by a team of psychologists organized by Samuel Stouffer and the observations of former journalist S. L. A. Marshall, the latter a persuasive, self‐promoting reserve officer who wrote convincingly if controversially of his after‐action interviews with infantry units. The research on the Wehrmacht did indeed show that German personnel assignment and training produced good infantrymen and cohesive units, but Shils and Janowitz underestimated the influence of Nazi ideology and the German Army's practice of field executions for desertion or non‐performance. Marshall stressed weapons employment and argued, without real statistical evidence, that the great majority of American soldiers did not shoot their rifles in combat—a conclusion partially supported by other analysis but also hotly contested. Marshall did identify real problems like overloading and fatigue, and he saw that the Germans stressed the use of crew‐served machine guns and mortars, which demanded teamwork and produced large enemy casualties.

The postwar army sought ways to improve the performance of its ground forces—especially infantry—through a variety of reforms and succeeded within tactical definitions under its control. One policy (adopted by all the services) was to rotate personnel on and off active operations. Aviation units had begun this practice in World War II for sound operational reasons. Ships also required periodic relief from operations for service and repair, and their crews benefitted.

The idea that large numbers of ground troops, especially enlisted men, would rotate out of combat, and even leave the service before a war ended, emerged during the Korean War (1950–51). In retrospect, combat effectiveness had little to do with the rotation policy. Equity in exposure to death and domestic politics had a great deal to do with the policy of limited liability, which was subsequently extended to the Vietnam War. Only about one‐third of the mobilized armed forces actually reached the Korean War theater; the rest remained in training in the United States or deployed to Europe. Individual reservists, especially World War II veterans, went off to fight, while National Guard and reserve units (with some exceptions) only served elsewhere. Sociologists like Janowitz and Charles Moskos reinforced the views of senior army officers that rotation weakened group cohesion and performance, but the policy was an effect, not a cause, of fighting an undeclared war with limited public support for limited goals and a negotiated (not imposed) armistice. Casualties reduce group cohesion, not rotation. The practice of conserving infantrymen by calling for deluges of artillery fire and close air support paradoxically produced excessive American casualties from so‐called friendly fire. Such a reliance also allowed many infantry units to avoid serious training and combat experience. One useful change by the army was the wider use of crew‐served weapons and the internal reorganization of squads into fire teams.

Problems that went unsolved in Korea returned in the Vietnam conflict, but as long as soldiers saw some prospect of victory, they fought well. The conduct of American soldiers and Marines well into 1969 showed superior training and commitment, even in a dubious cause. Limiting Vietnam tours of duty to twelve months gave some prospect of relief, though not much for infantrymen. It was hard for “grunts” to survive a year in the “bush” under the pressures of combat and disease. The most invidious policy was rotating officers out of infantry companies after six months when grunts had no such option. Committed warriors often actually extended their combat tours, but did so most often if they belonged to elite special forces or reconnaissance units, the ground equivalent of aviation fighter squadrons. Personnel policies that reduced group cohesion may have been counterproductive. The root cause, however, of undiscipline, malingering, drug use, and soldier crime against each other and civilians was the lack of belief in the war's value, and the widespread demoralization and even incompetence in the officer corps. Just how to deal with this potential problem remains unresolved, since post‐1975 operations in Grenada, Panama, and Kuwait did not last long enough or produce enough casualties to test group cohesion under sustained combat. Instead, the prevailing view is that sophisticated technology, massive firepower, low casualties, and unambiguous causes now characterize the American Way of War. Whether this combination constitutes combat effectiveness in every instance remains to be seen.
[See also Combat, Changing Experience of; Combat Support; Morale, Troop; Training and Indoctrination.]


Allan R. Millett and and Williamson Murray , Military Effectiveness, 3 vols., 1988.
Allan R. Millett and and Peter Maslowski , For the Common Defense: The Military History of the United States of America, 1984; rev. ed., 1994.

Allan R. Millett

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