The 100-year-old steel maker once known as Stelco Inc. will become independent again after United States Steel Corp. gave up on trying to restructure the company it purchased in 2007. U.S. Steel Canada Inc., possessing the youngest integrated steel mill in North America and an idle steel making mill in Hamilton, will proceed on its own or be sold after U.S. Steel and its stakeholders failed to reach a deal on the future of the Canadian unit within its troubled Pittsburgh-based parent company.