The Democratic Republic of Congo is talking to the United States in its bid to find an ally in the government’s battle against the M23 rebels. There are warnings that South Sudan risks sliding back to civil war after recent clashes and the arrests of some opposition leaders. Talk of tariffs combined with fears of inflation sent the U.S. stock market tumbling Monday and again on Tuesday, a day of give and take between the United States and Canada, with President Donald Trump defending his use of tariffs.