This is the USNS Comfort next to a Nimitz-class supercarrier, the biggest war ship in the world. Together with its twin, the USNS Mercy, they are the largest hospital ships on the oceans, the second largest hospital in the US and the fifth largest on the planet.
Their labor is admirable, helping tens of thousands all over the world every year.
Both ships are huge, 894-feet (272-meter) leviathans with a flight deck displacing 69,360 tons. They have a combined 2,000 beds, 24 fully equipped operating rooms, radiological services, medical labs, intensive care units, dental services, physical therapy and burn care, pharmacies, optometry labs, CAT scan and four oxygen factories. The Mercy also has a powerful Lumenis laser to treat patients.
The Mercy was originally the SS Worth supertanker, built in 1976. The Comfort was the exact same type of ship, a San Clemente Class oil tanker built in that same year. The 3-football field long ships were reconverted by the US Navy to treat injured soldiers everywhere.
But they do much more than that. Together with volunteers from non-governamental medical organizations, they also help tens of thousands of civilians affected by natural disasters. The US Navy's floating hospitals played a very important role in the aftermath of the Haiti earthquake, the Southeast Asia tsunami or Hurricane Katrina, to name just a few.
None of them carry offensive weapons—only defensive. Firing against both ships would be a war crime according to the Geneva Conventions. The crews on both ships are civilian, and they include hundreds of volunteer medical personnel, like the hundred volunteers from Project HOPE that, along with others from different NGOs, just returned from the Mercy's 2012 Pacific Partnership voyage to Southeast Asia.