According to a report in the the New England Journal of Medicine on Wednesday, fundamental changes in treating wounded troops have altered the old calculus for measuring a war's intensity.
Harvard professor Atul Gawande, also a surgeon at Boston's Brigham and Women's Hospital, concludes that it may therefore be misleading to focus only on combat deaths to gauge the level of fighting in Iraq.
Military doctors and nurses face significant challenges in Iraq, including a mysterious drug-resistant infection plaguing wounded soldiers and blast injuries that have caused an unprecedented burden of mangled limbs, he said.
Only about 10% of US soldiers injured in combat in Iraq and Afghanistan have died, Gawande said. That compared to about 25% for American soldiers injured while fighting in Korea, Vietnam and even during the Gulf war.
The flip side, however, is that for every 10 combat deaths, it must be assumed that about 10 times as many troops are injured, he said.
"When we hear that 10 soldiers were killed in fighting, we all draw a mental picture about what that means," Gawande said.
"But you have to multiply that number by 10 to find out how many were injured ... and that suggests a very different level of violence."
Gawande based his analysis on discussions with military surgical teams and official figures showing more than 10,700 US troops killed or wounded fighting in Iraq and Afghanistan.
That is more than the number of Americans killed or wounded in the US Revolutionary war and the first five years of the Vietnam war, but far below the hundreds of thousands of US casualties in the first and second world wars and the US Civil war.
"When we hear that 10 soldiers were killed in fighting ... you have to multiply that number by 10 to find out how many were injured ... and that suggests a very different level of violence"
Surgeon and Harvard professor
Gawande attributed part of the success in preventing combat deaths to better troop equipment such as Kevlar vests.
But he gave most credit to changes in the military's triage system and surgical teams that are leaner, more mobile and closer to battle - a "fundamental departure from previous wars".
Reason for improvement
The improvements are all the more remarkable given a shortage of medical personnel, Gawande said. Only 120 army general surgeons are on active duty and a similar number in reserve to support troops fighting in Iraq.
Some troops are surviving the loss of three limbs - which previously would have been uniformly fatal, Gawande said.
The US army disputed suggestions that the human cost of the war is being obscured, but acknowledged a relative increase in the number of injured limbs among US troops in Iraq.
Army medical officials said in a statement that extremity injuries are typically the most common in wartime, accounting for two-thirds of all wounds in most previous conflicts.
"However, the severity of the extremity wounds appears to have increased during this conflict," the statement said. It added this was most likely because similarly injured soldiers would have previously died from associated mortal wounds to the abdomen and chest.
No official figures are available for the numbers of Iraqi dead. Estimates have ranged from 14,000 to 100,000 civilians and about 5000 troops in the war.