Watch HDToday. When an international military treaty fell apart in the mid 1930s, America rebounded by building the most legendary battleships ever constructed; the Iowa class of battleship. USS Iowa BB-61 was the lead ship of the class and was of service for nearly 50 years. Ultimately, an on board catastrophe cut her service short, but her story continues today as the Iowa is a living museum. Together, veterans and historians tell her stories of tragedy and triumph.