How was World War I dehumanizing for the soldiers who fought in it?

All wars are brutal and ugly and ultimately dehumanizing to many affected by them, including civilians subjected to bombings and invasions and soldiers treated like expendable cogs serving interests they don't always understand. While many wars are fought for legitimate reasons, such as the efforts to defeat Nazi Germany and Imperial Japan during World War II, others begin as heroic responses to tyranny but turn into protracted quagmires from which there is no easy escape. Vietnam War veteran-turned-author Philip Caputo wrote in the prologue to A Rumor of War about how that particular conflict, at least for the soldiers directly involved, "had begun as an adventurous expedition [that] had turned into an exhausting, indecisive war of attrition in which we fought for no cause other than our own survival." That observation by one who fought in Vietnam and witnessed first-hand the moral complexities involved in waging a war of limited objectives -- preventing South Vietnam from being overrun by the Communist north -- remains as powerful and universal as any one will find among the vast literature of war.

World War I was a very unique conflict. The first major war of a still-new century, that conflict saw the introduction of terrifying new means of destruction, including the large-scale use of machine guns, the first use of tanks, the use of aircraft to strafe troops on the ground and to drop bombs from above, and, most disturbing of all, the use of chemical weapons. The technological sophistication of these means of destruction contrasted radically with the most enduring characteristic of World War I, the trench warfare that defined it. And it was the trenches in which the war proved dehumanizing for those subjected to them. While all wars are dehumanizing to many involved, and while the casualty figures associated with World War I are no worse than for wars that preceded and succeeded it, life in the trenches was dehumanizing for the obstacles soldiers confronted, especially during the cold winter months. Soldiers in the trenches were faced with disease and infestation, including rats and lice, in addition to the indignity of having to crouch or stand in mud trenches waiting for the next wave of enemy soldiers to attack or, even worse, for the next flare or whistle signaling the beginning of another human wave attack by one's own army. Racing from the trenches into the brutal fire of enemy machine guns and the terrifying specter of death or injury by inhalation of gas all because the powers-that-be had marched inexorably into a massive war for which they were not prepared was certainly dehumanizing. Living among rats and lice while sleeping in mud trenches in the brutal cold was entirely dehumanizing to those who fought there.