U.S. Adopts Tougher Stance on China By SEWELL CHAN WASHINGTON — The Obama administration is moving to take a harder stance on the Chinese government’s trade and currency policies, with anger toward China rising in both political parties ahead of midterm elections. Treasury Secretary Timothy F. Geithner, in separate hearings before House and Senate panels, plans to acknowledge on Thursday that China has kept the value of its currency, the renminbi, artificially low to help its exports and has largely failed to improve the situation as it promised to do in June. “We are concerned, as are many of China’s...