A Boeing Co. decision to locate a second 787 production line in South Carolina would cost Washington jobs, but the company has been exporting work for years, with little chance of a turnaround, an industry analyst says. Whether or not Charleston or Mobile, Ala., bid successfully for new U.S. aerospace plants, says Scott Hamilton, Boeing and the other major players in the industry today — Airbus, Bombardier and Embraer — are breeding future competitors in Japan, China and Russia.