The U.S. Merchant Marine is a fleet of civilian ships that transport goods and materials during peacetime and support military operations during wartime. It plays a crucial role in the nation's economy by facilitating international trade and ensuring the supply of essential goods. Merchant mariners are the trained professionals who operate these vessels. They are responsible for navigating, maintaining, and managing the ships, ensuring safe and efficient transport. The U.S. Merchant Marine also provides vital support to the U.S. Navy during conflicts, helping to move troops and supplies where they are needed.