Hanson, an economist and trade specialist at the University of California, San Diego (UCSD), says the biggest drop in manufacturing employment — from 17 million to 11 million between 2000 and 2010 — is mainly due to trade with China and underlying technological changes. “China tops the list in terms of the impact on jobs we`ve found since 2000, with technology in second place and NAFTA much less important,” he says. Overall, Canada has become more dependent on trade with the United States and has relied on its southern neighbour for 75 per cent of its exports. Other high-income countries tend to be much more diverse and rarely rely on a single partner for more than 20%. U.S. presidents have long had cordial relations with Canadian prime ministers, but Mr. Trump has not hesitated to use this dependence as a means of pressure. As part of the USMCA talks, he threatened new tariffs on Canadian auto parts if Ottawa did not accept trade concessions.