Cmdr. Tim Williamson, a U.S. Coast Guard Atlantic Area Lant-532, gives a presentation on maritime interdiction and operations to a group of international mariners in Cartagena, Colombia for the annual UNITAS exercise Sept. 1, 2018. The overarching goal of UNITAS is to develop and test command and control of forces at sea with multinational maritime forces, training in a wide spectrum of maritime operations.