Flag of Convenience
Cruise ships often run with what is known as a flag of conveninece. This means that the ship is owned by a company in one country - but is registered in and flies the flag of another.
The reason ships do this is for tax reasons. Everything tends to come down to money :) In international waters, a ship is subject to the laws of the country whose flag it flies. Many countries have made a speciality of offering ship registrations. They set up cheap fees, low taxes, low minimum wages, ship-friendly laws and low inspection requirements in order to gather all that money from ships.
Three main countries used for ship registrations are Liberia, Panama and the Bahamas. In recent times, several cruise ships have left Liberia out of concern that the funds were being used to give money to armies.
For practical reasons, it doesn't really matter which country's flag your cruise ship is flying. You normally go nowhere near the registration country. You go from your departure port, through a route and back home again. The crew tends to come from whereever labor is cheapest - or if anything, from the area of the owners.
It's almost certain that the registry will NOT be US - because ships want to stay away from the high taxes and strict regulations involved. Ship owners don't want to pay the high US minimum wages to their employees. A non-US ship isn't subject to the US ADA (Americans with Disabilities) Act.
So whichever ship you're on, you need to do research into what that ship actually offers. Don't assume it'll have certain ramps or regulations in place - make sure!
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