"Another one from SF would be SF-Monterrey-Morro Bay -Santa Barbera-Catalina Island-LA or back to SF. The possiblities for shore excursions would be fabulous. Of course they'd have to repeal the Hayes Act (what good does it do these days anyway?) I guess the ship could make a run to Ensenada or Rosarita Beach unless Catalina decided to declare it's independance. "
Actually, it's the Jones Act that's the problem. Basically, the Jones Act has two crucial requirements.
>> 1. A ship of foreign flag must call at a foreign port before disembarking passengers at a port of origin in the United States if it makes any ports of call after departing from the port of embarkation. (The law permits a "cruise to nowhere" because a ship must be able to return to its port of departure without penalty in an emergency.)
>> 2. A ship of foreign flag must call at a "DISTANT" foreign port befroe disembarking passengers who embarked at any U. S. port at any other U. S. port. (Basically, the ports of Europe, Asia, Africa, South America, Australia, New Zealand, Oceana, the Caribbean islands of Aruba, Bonaire, and Curacao, and the territorial islands of countries that qualify as "distant" are considered to be "distant" under the Jones Act. This isn't quite precise, but close enough for the present discussion.)
The government levies a fine against the cruise line of $2,000 per passenger who disembarks illegally, so all cruise lines have pretty strong incentive to comply. Note the following, by way of example.
>> Princess's "Panama Canal Adventure" itineraries between California (San Diego, Los Angeles, or San Francisco) and Florida all call at both Cartagena, Columbia (or Colon, Panama, while calls at Cartagena remain suspended) and Orangestad, Aruba, which are distant foreign ports.
>> Princess's "Canada and Colonial America" itiernary along the East Coast of the United States at the end of the "Canada and New england" season always originates in Montreal rather than New York.
>> Norwegian Cruise Line's cruise around the Hawaiian Islands also calls at Fanning Island, which is part of Kiribati -- actually a "distant" foreign port even though a "near" foreign port would be acceptable.
>> All of the "Caribbean" and "Mexican Riviera" itineraries that operate from U. S. ports return to their respective ports of embarkation.