The United Steelworkers union is calling on the United States to impose higher tariffs on aluminum imports, the New York Times reports.  On Monday, the union’s law firm filed a petition under Section 201 of the 1974 Trade Act, which permits “domestic industries seriously injured or threatened with serious injury by increased imports [to] petition the United States International Trade Commission (USITC) for import relief.”  According to the union, the U.S. aluminum smelting industry is suffering: by this summer, over three-quarters of the industry that existed five years ago will have been idled or shut down.  The union cites China’s rising exports as a key reason for the industry’s decline.