Infantry

Infantrymen engage the enemy in close combat, sometimes hand-to-hand, standing on their feet, lying on the ground, or dispersed in holes which they have found or dug in the dirt. In battle, and sometimes between battles, they must carry everything they need to fight and survive on their persons.

Infantry can be categorized by how much they must rely on their own physical strength and endurance, separated from mechanical support. Special Operations Forces (the "Green Berets") and Rangers are all airborne (parachute) qualified, but may undertake prolonged and grueling missions, with only rare, air-dropped supplies. Airborne infantry are delivered by parachute or airlanding, but are reinforced by heavier units within a few days and continue to fight as light infantry. Light infantry and air assault infantry also must travel very light on the ground, but usually have helicopters and a few light trucks for rapid redeployment and resupply.

Infantry make up the most numerous component of most combat forces. Because of their relative numbers and the degree of unprotected exposure to enemy weapons and the elements, they usually suffer the highest number of casualties and make up a large percentage of the battle fatigue cases. However, the percentage of battle fatigue casualties to killed and wounded among well-trained infantry units is typically lower than in armor, artillery, or combat services support units. An average rate for conventional combat is one battle fatigue casualty per five wounded, with at least an equal number treated and returned immediately to duty. Rates of 1:3 to 1:2 are seen in very prolonged and especially static combat.

In the elite special forces, ranger, and airborne units, the ratio has been strikingly low (less than 1:10 or 1:20) even in mass casualty battles. This is attributed to the benefits of tough training, close contact with trusted leaders and comrades ("vertical and horizontal unit cohesion"), and a sense (most of the time) of having some personal control over one's fate. The ground is the infantryman's protection, allowing dispersion and shelter if wisely used. To quote a Bill Maudlin World War II cartoon, Joe is looking at a tank and says to Willie, "I'd rather dig. A moving foxhole attrac's the eye." Mines, booby traps, and chemical contamination of the ground (requiring wearing of the protective ensemble) make the ground no longer a reliable friend, and are therefore especially stressful.

Infantry soldiers are especially prone to combat exhaustion as they are deployed rapidly and are subject to extreme physical work, sleep loss, and limits on available food, water, and hygiene. They can often feel unprotected or unsupported in the field of operations. Communication can get very difficult, especially at night or in restrictive terrain when visual contact with the rest of the unit may be nearly impossible. Often moving quickly through difficult terrain or behind enemy lines, the special operations forces (SOF), light infantry, or mechanized infantry soldiers can become separated and anxious about being wounded and left on the battlefield. While this may heighten the soldiers' sense of unit cohesion, the effect of a lost or wounded member on the whole unit can be devastating.

It is in the field of battle that unit bonds are often tested and an entire unit can be immobilized or destroyed because of the one weak link in communication or trust. Prior to mobilization the unit members must get to know each other and especially to be confident in each of their abilities to fight together as a team. No unit should be deployed without the commander's having the opportunity to portray himself as a thoughtful and knowledgeable leader; a unit without confidence in its leader can fail, generating a large percentage of both emotional and physical casualties.

Because of the newer weapons technologies and the rapidly moving forward edge of the battlefield, fragmentation among infantry units can often occur. Devastation of life by enemy or friendly fire may be great, and the exposure to dead and wounded comrades as well as enemy is magnified. In this setting, human soldiers must often charge ahead and their sense of "neglecting" their buddies is intense. Sensory overload under these conditions can only be countered by the unit cohesiveness and bonding developed long before the mission is begun.

Ongoing development and testing for the "digital battlefield" of the "Information Age" of the 21st century proposes to give each infantry fire team leader, and perhaps each infantryman, a global positioning device that gives precise coordinates for his location on the terrain and short-range voice communication with other team members. There may even be a "heads-up" display inside the visor to his helmet that advises him of the locations of all other friendly forces and identified enemies in the vicinity, as well as much other information. Assuring that this technology increases combat effectiveness rather than creating distraction and dependency, especially in tired, fearful soldiers, will be an urgent topic for combat stress control in future field trials, training, and combat operations.