The announcement of a deal between United States and Mexico on the renegotiation of the North American Free Trade Agreement paves the way for Canada to return to the talks, but negotiators face several politically fraught issues before a trilateral deal can be reached. Canadian Foreign Affairs Minister Chrystia Freeland, Ottawa's lead in the talks, has not been a part of the discussions between the U.S. and Mexico over the last five weeks -- and she is scheduled to be...