Yup...that's a better idea.........
A cruise ship "is" a Petri dish, but it is also an ideal quarantine facility. After two weeks, they can be docked and go home.
Not really. As we are seeing on the Japanese ship, rooms all share an air system, food source and the virus is likely airborne. The crew is not trained for this kind of contamination control. Every time a positive test comes up, the clock resets to 14 days. They need to be in real quarantine with correct infection control. The Japanese ship went from one passenger on the previous cruise infected to 64!