What is war good for? Absolutely nothing, according to the 1970 protest song. History tells a different story. Wars cause death, disability, and disease on devastating scales. But they also lead to dramatic advances in medicine—and, in World War I at least, for women.

The battlefield has always provided doctors with unique opportunities to practice and improve their skills. The Greek father of medicine, Hippocrates, advised, “He who wishes to be a surgeon should go to war.” The sheer scale of casualties and range of injuries warfare produces have given surgeons in the past—and today—experience they never normally encounter in civilian life, forcing them to test and perfect new techniques. Diseases which can assume epidemic proportions in war challenge physicians to devise new therapies and methods of containment.