Although the Washington Naval Treaty put a stop to the battlecruiser program, it did permit both Japan and the United States to convert two of their battlecruisers, then under construction, into aircraft carriers. In its more than two-century history, the United States Navy has frequently taken ships designed and built for one purpose and rebuilt and rearmed them for an entirely different mission. A brief historical review of what was done and why leads to a discussion of what repurposing possibilities exist in the 21st century.In 1814, the United States Navy launched Independence, its first ship-of-the-line. A powerful warship, she had three gun decks and carried a heavy armament of eighty-seven cannons, firing 32-pound cannonballs. Unfortunately, Independence had a significant flaw. She rode so deep in the water that the gun ports on her lower gun deck were less than four feet above the waterline. Unless sailing in calm seas, the ship dared not open the gun ports on her lower gun deck for fear of flooding. Consequently, in most sea conditions, Independence could not employ a third of her armament.