I do not know if any of this will advance the discussion but it makes interesting reading.
Napoleon stated that the moment of greatest danger was the instant immediately after victory, and in saying so he demonstrated a powerful understanding of the way in which soldiers become physiologically and psychologically incapacitated by the parasympathetic backlash that occurs as soon as the momentum of the attack has halted and the soldier briefly believes himself to be safe. During this period of vulnerability a counterattack by fresh troops can have an effect completely out of proportion to the number of troops attacking.
It is basically for this reason that the maintenance of an "unblown" reserve has historically been essential in combat, with battles often revolving around which side can hold out and deploy their reserves last. Clausewitz understood the danger of reserve forces becoming prematurely enervated and exhausted (and he provides insight into the root cause of the enervation) when he cautioned that the reserves should always be maintained out of sight of the battle.
In continuous combat the soldier roller-coasters through a seemingly endless series of these surges of adrenaline and their subsequent backlashes, and the body's natural, useful, and appropriate response to danger ultimately becomes extremely counterproductive. Unable to flee, and unable to overcome the danger through a brief burst of fighting, posturing, or submission, the bodies of modern soldiers in sustained combat exhaust their capacity to enervate. They slide into a state of profound physical and emotional exhaustion of such a magnitude that it appears to be almost impossible to communicate it to those who have not experienced it.
The full link is at http://solutions.synearth.net/2002/10/18
The following link is about the U. S. Civil War [and later conflicts], but I think can be applied to our era as there are still many similarities between the campaigns.
Someone else noted about Post Traumatic Stress Disorder: "In the Napoleonic Wars it was referred to as "nostalgie" or homesickness. In the Civil War it was called "irritable heart." It was thought that only cowards suffered from these problems and that it manifested itself in only a small minority of those involved in actual combat. In WWI, victims were recognized as suffering from "shell shock." Again, only a small minority were found to be suffering its effects, but at this time the origin was believed to be physiological—actual physical damage caused from shells exploding too near a soldier. In WWII, the description was changed to "battle fatigue," more closely reflecting the true cause and acknowledging the emotional and psychological nature of the disorder."
NOSTALGIA: REDISCOVERY OF A CONCEPT
Nostalgia was a medical concept recognized even before 1678, when the Swiss physician Hofer created this term to describe soldiers previously labeled as suffering from "Das Heimweh" or homesickness.
Earlier in the 17th century, soldiers in the Spanish Army of Flanders were stated to suffer from "mal de corazon" ("illness of the heart"), and Swiss mercenaries in France were said to suffer from "maladie du pays" ("homesickness"). Because the majority of such soldiers were mercenaries uprooted by financial exigencies from their farms in Switzerland, these soldiers were often described as suffering from "the Swiss disease." The critical variable was service, often involuntary, far from one's country, family, and friends. By the middle of the 18th century, nostalgia was a well-defined nosologic entity recognized as afflicting not just Swiss soldiers but potentially any soldier displaced from his milieu of origin, and generally was considered to be a mental disorder. The symptomatology associated with nostalgia was consistently compatible with modern descriptions of depression, with complaints, for example, of "moroseness, insomnia, anorexia, and asthenia" in a report by Sauvages in 1768. Even this early there were observations that nostalgia might be feigned as a method of avoiding duty. A French physician, De Meyserey, who published a treatise on military medicine in 1754, observed that war and its dangers always produced a fruitful crop of malingerers who must be discriminated from soldiers with "true nostalgia."
Baron Larrey, Napoleon's Chief Surgeon, prescribed a course of treatment which, while ostensibly biologically oriented, reveals a keen awareness of social factors and is surprisingly close to modern handling of combat psychiatric casualties, both preventively and curatively. He stated that it is necessary not to allow individuals who are predisposed to nostalgia more rest than is necessary, to vary their occupations, and after military exercises to subject them to regular hours, gymnastic recreation, and some mode of useful instruction. He also stated that they should have mutual instruction with troops of the line and that warlike music will contribute to preventing gloomy reflections which can lead to nostalgia. This would ensure physical bodily integrity, produce a conviction: of health, give a sense of mastery of weapons, and integrate the unit. This regimen prevents evacuation home (the treatment approach of earlier physicians) and minimizes any secondary gain from illness.
During the Civil War, Calhoun ascribed a relationship between nostalgia and the recruiting methods of the Union Army that could have parallels with the "nostalgic casualties" of the Vietnam conflict. Calhoun described initially enthusiastic soldiers who had expected an early end to the conflict and who became disenchanted as the war dragged on. The statistics on desertion, draft dodging, and similar attempts to avoid duty were not much different during World War II, a more popular war, and the Vietnam conflict (in fact, these rates were generally lower during Vietnam than during World War II). This suggests that the disenchantment toward the end of the conflict in Vietnam may not have been as important a factor in generating nostalgic casualties as the loss of unit cohesion. Nostalgic casualties occurred in soldiers separated from their home environment with attendant loss of social reinforcement.
Situations such as the fighting of an unpopular war of indefinite duration are likely to increase these casualties, particularly in the absence of strong cohesive forces, which usually develop from shared hardship and danger. Hence, Calhoun cited battle action as a curative factor in nostalgia:
'Their thoughts were turned from home, and they felt they were men and soldiers, peers of the veterans with whom they associated; and from that day to this there has been but little or no sickness, and but one or two deaths...When men have passed through the baptism of fire together, they feel they have something in common. They have a common name, a common fame, and a common interest which diverts their thoughts away from home.'