The Jones Act requires cargo ships traveling between U.S. ports to be built in the U.S., owned by U.S. companies, employing only U.S. workers. That means a ship from Asia can’t stop in Hawaii, drop off food and other products, pick up other cargo and continue to the West Coast. As a result goods are generally shipped to the mainland and then from the mainland to Hawaii. That’s one reason why things are so much more expensive in Hawaii.
Secretary-designate Buttigieg supports this because unions like it, and West Coast Senators like it, and the voices of the poor in Puerto Rico who are kept poor aren’t heard nearly as loudly.