Another casualty of modern combat is the military hospital ship. Only the United States still deploys these floating hospitals. America has two of them, built in the late 1980s. Each has a thousand beds and extensive facilities for all manner of medical treatment. But the 70,000 ton ships require 1300 sailors and medical personnel to run. Its more effective to have better equipped medical teams closer to the fighting, and then fly the badly wounded troops to better equipped hospitals in the United States or Europe (where the American military has extensive medical facilities.) Improvements in medical equipment, and instant operating rooms (climate controlled shelters that can be erected in minutes) make it all possible. In addition, its cheaper to do the up close and personal approach than to fly the wounded back to a helipad on the hospital ship. Moreover, with a thousand hospital beds and a dozen operating rooms, theres much more capacity than is needed. The casualties in Iraq are easily handled by the hospital facilities ashore. This will end over a century of use, as the first modern hospital ship was built, by the United States during the 1898 Spanish-American war, and by Japan, to treat both Japanese and Russian casualties during the 1904-5 Russo-Japanese war. 

Ships specializing in medical care were used before, at least as early as ancient Greece. But the modern hospital ship, carrying with it medical facilities rivaling the best hospitals ashore, is very recent. The first one was the USS Solace (later given the designator AH-2), built as a freighter in 1897 and acquired by the Navy the following year. She was extensively outfitted with the most modern facilities, including x-ray, and served into the 1920s. For many years she was probably better equipped than most small town hospitals. Most hospital ships were conversions from merchant ships. The one American exception was USS Relief (AH-1), which could handle c. 600 patients. Commissioned in 1920, she served through World War II. She was actually built from the keel up as a hospital ship.