Canada&#8217;s Foreign Minister Chrystia Freeland, left, Mexico&#8217;s Economy Secretary Ildefonso Guajardo Villarreal, center, and U.S. Trade Representative Robert Lighthizer shake hands after posing for a group photo at a press conference regarding the second round of NAFTA renegotiations in Mexico City, Tuesday, Sept. 5, 2017. (AP Photo/Marco Ugarte) MXMU120