An underwater salvage company was granted approval this week to cut into the wreckage of the Titanic to try to recover a Marconi telegraph, rekindling a complex debate over access to the ship and maritime law. The company, R.M.S. Titanic, persuaded a federal judge on Monday to allow it to conduct a salvage operation this summer in the wreckage of the ship, which sank during its maiden voyage across the Atlantic in 1912 after hitting an iceberg. More than 1,500 of the ship’s passengers died, and about 700 survived. The ruling, by Judge Rebecca Beach Smith of the U.S. District...