We'll fight 'em and we'll win

Trade wars are easy.

Canadian Prime Minister Justin Trudeau said that a NAFTA deal was within reach when Vice President Mike Pence scuttled it by demanding the inclusion of a “sunset” clause that would automatically expire the pact in five years, according to a Thursday Washington Post report.

Trudeau told the Washington Post that he was planning a trip to D.C. to finalize the deal when Pence called with his ultimatum. “I had to highlight that there was no possibility of any Canadian prime minister signing a NAFTA deal that included a five-year sunset clause, and obviously the visit didn’t happen,” Trudeau said.

The White House fired back at Trudeau in a Thursday statement. “That United States has been taken advantage of for many decades on trade. Those days are over,” it read. “Earlier today, this message was conveyed to Prime Minister Justin Trudeau of Canada: The United States will agree to a fair deal, or there will be no deal at all.”

This breakdown happened in the midst of President Donald Trump’s decision to levy stiff tariffs on steel and aluminum imports from a swath of American allies including Canada and Mexico, provoking likely retaliation and a possible all-out trade war.

Per the Washington Post, Trump has said that the tariffs are necessary for U.S. protection, though they have been criticized by groups as disparate as foreign leaders, American business leaders, and American labor organizations.
  TPM

So, Trump threw down tariffs on Canada (as well as Mexico and the EU) because the trade talks broke down. Looks like maybe Pence is the one who broke them, and that wouldn't have happened without Trump's order.

...but hey, do what you want...you will anyway.