Almost eighteen million men served in World War II. Volunteers rushed to join the military after Pearl Harbor, but the majority—over 10 million—were drafted into service. Volunteers could express their preference for assignment, and many preempted the draft by volunteering. Regardless, those recruits judged I-A, “fit for service,” were moved into basic training, where soldiers were developed physically and trained in the basic use of weapons and military equipment. Soldiers were indoctrinated into the chain of command and introduced to military life. After basic, soldiers moved onto more specialized training. For example, combat infantrymen received additional weapons and tactical training and radio operators learned transmission codes and the operation of field radios. Afterward, an individual’s experience varied depending upon what service he entered and to what theatre he was assigned.

Soldiers and marines bore the brunt of on-the-ground combat. After transportation to the front by trains, ships, and trucks, they could expect to march carrying packs weighing anywhere from 20-50 pounds of rations, ammunition, bandages, tools, clothing, and miscellaneous personal items in addition to their weapons. Sailors, once deployed, spent months at sea operating their assigned vessels. Larger ships, particularly aircraft carriers, were veritable floating cities. In most, sailors lived and worked in cramped conditions, often sleeping in bunks stacked in rooms housing dozens of sailors. Senior officers received small rooms of their own. Sixty-thousand American sailors lost their lives in the war.

During World War II the Air Force was still a branch of the U.S. Army. Soldiers in the served on ground crews and air crews. World War II saw the institutionalization of massive bombing campaigns against cities and industrial production. Large bombers like the B-17 Flying Fortress required pilots, navigators, bombardiers, radio operators, and four dedicated machine gunners. Soldiers on bombing raids left from bases in England or Italy, or from Pacific Islands, endured hours of flight before approaching enemy territory. At high altitude, and without pressurized cabins, crews used oxygen tanks to breath and on-board temperatures plummeted. Once in enemy airspace crews confronted enemy fighters and anti-aircraft “flak” from the ground. While fighter pilots flew as escorts, the Air Corps suffered heavy casualties. Tens of thousands of airmen lost their lives.

On-the ground conditions varied. Soldiers in Europe endured freezing winters, impenetrable French hedgerows, Italian mountain ranges, and dense forests. Germans fought with a Western mentality familiar to Americans. Soldiers in the Pacific endured heat and humidity, monsoons, jungles, and tropical diseases. And they confronted an unfamiliar foe. Americans, for instance, could understand surrender as prudent; many Japanese soldiers saw it as cowardice. What Americans saw as a fanatical waste of life, the Japanese saw as brave and honorable. Atrocities flourished in the Pacific at a level unmatched in Europe.