The Jones Act, officially known as the Merchant Marine Act of 1920, is a U.S. law that regulates maritime commerce. It requires that goods transported between U.S. ports be carried on ships that are built, owned, and operated by American citizens or permanent residents. This law aims to support the U.S. shipping industry and ensure national security. The Jones Act also plays a significant role in the economy of U.S. territories, such as Puerto Rico. It can affect the cost of goods and services in these regions, as they rely heavily on maritime transport. Critics argue that it leads to higher prices, while supporters believe it protects American jobs and the maritime industry.