This book traces the evolution of the role of the U.S. Merchant ship flag, and the U.S. merchant fleet itself, from the earliest days of the American Republic to the present. The book shows how the protection of the U.S. flag aboard merchant ships was often the cause for U.S. naval engagements, ranging from minor incidents through full-blown, declared wars. It also spells out how in the 20th and 21st centuries, the American-owned merchant fleet has "fled" from the U.S. flag to foreign registries, under flags of convenience. Many other maritime nations have experienced the same development in recent decades, and the world-wide development of this practice, as well as measures to off-set its ill effects are examined.