I was just curious as to what the country of registry really means? On the back of the ships and on the commercials it always shows Bahamas, Liberia, Panama, etc....what does this mean and what is the big deal with NCL's U.S. registered ships?
Each commercial vessel must be registered in some country which will determine the gross and net vessel weights, issue required registration documents to the ship, collect appropriate taxes, fees, etc. The vessel also flies the flag of that country.The so-called "countries of convenience" to which you referred ( Liberia, etc.) document ships at the lowest costs and are therefore the most popular with the corporate owners.
As for the NCL's gambit: foreign-flag ships are not permitted to carry passengers from one U.S. port (e.g. Honolulu) roundtrip to a U.S. port (again Honolulu) without a stop at a foreign port (e.g.,in NCL's case, Fanning Island in the Republic of Kiribati). But they lose 2 days sailing to Fanning and back. By now registering 2 ships under the U.S. flag, they avoid the trip to Kiribati & can now extend their coverage of the Hawaiian Islands. They will also be staffing their 2 ships with American crews. Jack
There's no quick answer to your question, so here goes.
An 1886 law called The Passenger Service Act is a part of U.S. cabotage (coastwise) laws and basically prohibited foreign-flagged vessels from carrying passengers "...between ports or places in the United States either directly or by way of a foreign port...." A subsequent exception to this law provides that foreign-flagged cruise ships may carry passengers from a U.S. port as long as they return them to the same port (a "voyage to nowhere"), and also permits foreign ships to call at intermediate U.S. ports as long as 1) no passenger permanently leaves the vessel at those ports, and 2) the vessel makes at least one call at a foreign port. That explains the NCL trip to Kiribati and back.
There are many advocates for reform of the U.S. cabotage laws, which were originally enacted to protect national defense interests by preserving both an active merchant marine and a domestic shipbuilding industry. They were also intended to protect our economic interests (U.S. jobs & businesses) from foreign competitors. The reformers point out that times have changed and that cruise ships today primarily provide entertainment services and are rarely used as a method of transportation from one place to another. They also point out that no U.S.-flagged ocean-going passenger vessels have been built in the U. S. since 1951. But the law stands until Congress decides to change it, and that may be a long way off.
In addition you cannot flag a ship to the USA unless the ship is actually built in the USA and staffed by Americans. This all increases the costs considerable over and above the taxes, wages, etc that must be met. The United States was constructed in the USA and even though it is nothing more than a hull at present it meets the requirements so therefore it will be allowed if registered in the USA and staffed by Americans to sail up and down the Eastern Seaboard which is NCL's intentions.