Opposition inside and outside the US

Executives are increasingly concerned that Trump may tear up NAFTA and they're getting ready.

Corporate leaders are banding together to tell Trump that their supply chains depend on predictability from NAFTA.

At the same time, Canadian foreign affairs minister Bob Nault asked Congress to weigh in.

"The last time I looked, the U.S. is not a dictatorship, and neither is Canada or Mexico. So this isn't about one individual, whether it is the president of the United States or the prime minister of Canada."

"The role that Congress plays is very, very important and if the government of the United States and its representatives is not interested in the deal they should probably tell us and not put forward pieces of work that they know we would never agree to at the negotiating table."

Ultimately, Trump may face the decision of grandstanding on NAFTA, tearing up the deal and fighting it out in the courts, or accepting cosmetic changes to the agreement and declaring a hollow victory.

With Trump, you never know.