China has added its currency to the weapons it is willing to use in the trade war with the U.S., and it is now up to President Donald Trump to determine how much further the situation can escalate. China on Monday allowed its currency to slide below what has been a psychological red line—the key 7 yuan to the dollar level — for the first time since 2008. China also halted new purchases of U.S. agricultural products, according to state run media. The Chinese picked two sore spots for Trump, who has protested the strong dollar and railed against other countries he says are weakening their own currencies for trade ... (full story)