The administration of U.S. President Joe Biden said Wednesday it will seek to triple the tariff rate on steel and aluminum imports from China, in an attempt to deal with what it sees as its “unfair practices” and protect American workers. Senior administration officials said Biden will touch on the plan when he delivers a speech in the afternoon at the United Steelworkers headquarters in Pittsburgh, Pennsylvania, a key battleground state in the presidential election in November. Currently, the average tariff rate on steel and aluminum products from China is 7.5 percent, according to the White …