Most of the casualties in Iraq and Afghanistan are not caused directly by combat. Meanwhile, one of the more dramatic changes in warfare during the last decade has been the dramatic change in the pattern of wartime combat casualties. The most notable change was the sharp drop in the number of American combat dead. The combat death rate in Iraq was a third of what it was in Vietnam and World War II. With the dramatic drop in combat deaths, came another big shift. In World War II, one in three casualties was killed. In Iraq and Afghanistan, only 12 percent of the casualties were fatal. This does not change the dramatic difference between combat losses then and now. In World War II, U.S. divisions suffered about 60 dead and wounded per combat day, while in Iraq there was been 3.5 (during the period of peak combat) per combat day, and in Afghanistan, even less. So by any measure, U.S. troops have learned how to avoid getting hit. The reasons are better equipment, tactics, weapons, leadership and training than in the past. With an all-volunteer force, the troops are smarter and more physically fit than in the past. Many of the life-saving innovations U.S. troops have come up with in the past decade have not gotten much publicity. Good news doesn't sell, but in this case, it has definitely saved lives.
There are still lots of casualties, but most of them from non-combat causes. During the peak period of combat (2004-7), 34,000 American troops were evacuated out to obtain more advanced care elsewhere (U.S. military hospitals in Europe and the United States). That was about six percent of the troops who were there during that period. Most of those who were sick or wounded were not evacuated (minor injuries were treated and the patient returned to duty), meaning that nearly 15 percent of the troops were sick, injured or wounded while in the combat zone.
Those evacuated had the most serious conditions, and the most common (24 percent) was muscular problems (including back pain and repetitive stress). Next came combat injuries (14 percent). Then came neurological problems (10 percent), psychiatric problems (9 percent) and spinal pain (7 percent). The rest (36 percent) consisted of a wide variety of problems (infections, respiratory problems, gastrointestinal, pregnancy, tumors, and hormonal problems.)
A lot of the illness related problems had to do with the different mixture of microbes in the region. This produces the same array of problems tourists encounter when they visit someplace quite different from home. A major source of injuries was traffic accidents, and the stress of carrying heavy weights (usually by the infantry, but supply troops and engineers also suffer from this).
Then there is stress. During this period, for every soldier killed in combat, at least one was sent back to the United States because of severe PTSD (post-traumatic stress disorder), and several others are treated in the combat zone for less severe cases. During World War II, PTSD was an even more serious problem. In the European Theater, 25 percent of all casualties were serious PTSD cases, compared to about 20 percent today. In the Pacific Theater, the rate varied widely, depending on the campaign. In some of the most intense fighting, like Okinawa in 1945, PTSD accounted for over a third of all wounded. In Iraq, less than ten percent of the wounded are PTSD, but the more troops serve in a combat zone, in combat jobs, the more likely they are to develop PTSD. This has been known for over a century.
War has always been hard on the troops, but the majority of danger didn't come from enemy action.