The U.S. Navy is already operating the Triton drone boat near Iran, and more Tritons could soon be used to counter China and other adversaries in the world’s waters. The autonomous sailboat-turned-submarine can carry various payloads, and since it’s powered by solar panels, it can sail autonomously for months at a time. Military experts say drones like the Triton could be used for various offensive and defensive purposes, from defending ports and monitoring underwater pipelines to laying sea mines and attacking Navy ships. WSJ’s Shelby Holliday got a closer look at the stealthy ocean drone.Chapters:0:00 The Ocean Aero Triton0:38 The system3:27 The uses 4:31 The future