After its unmanned vessels recently drew attention in the Iran war, Saronic Technologies, a shipbuilding start-up, announced on Thursday that it would open a new facility in the United States to make both naval and commercial ships. Saronic’s chief executive, Dino Mavrookas, said the company would break ground this year on an 850-acre shipyard in Brownsville, Texas, and begin building vessels there by 2028. Last month, the U.S. military used a Saronic drone boat to rescue the two-person crew of a downed Apache attack helicopter off the coast of Oman. This week, three of its vessels were used to attack...