Growing objections within Member States to U.S. trade policy and various aspects of the USMCA have had an impact on the signing and ratification process. Mexico said it would not sign the USMCA if tariffs on steel and aluminum were maintained. [62] Based on the results of the November 6, 2018 U.S. election, it has been speculated that the greater power of Democrats in the House of Representatives could jeopardize the passage of the USMCA agreement. [63] [64] Bill Pascrell, a senior Democrat, argued for changes to the USMCA to pass Congress. [65] Republicans have opposed the USMCA provisions that impose labour rights on LGBTQ and pregnant workers. [66] Forty Republicans in Congress have asked Mr. Trump not to sign an agreement that includes “the unprecedented integration of sexual orientation and the language of gender identity.” As a result, Trump ultimately signed a revised version that required each nation only to “policies it deems appropriate to protect workers from discrimination in the workplace” and said the United States would not be required to introduce additional non-discrimination laws.

[67] The Canadian government expressed concern about the changes that have occurred under the USMCA agreement. [68] On June 1, 2020, the USTR Office issued the uniform rules,[30] the last hurdle before the implementation of the agreement on July 1, 2020. Economists largely agree that NAFTA has benefited North American economies. Regional trade increased sharply in the first two decades of the treaty, from some $290 billion in 1993 to more than $1.1 trillion in 2016. Cross-border investment has also increased and U.S. direct investment (FDI) in Mexico has increased from $15 billion to more than $100 billion during this period. But experts also say it has proved difficult to highlight the direct impact of the agreement from other factors, including rapid technological change and expanded trade with countries such as China. In the meantime, discussions continue on the impact of NAFTA on employment and wages.

Some workers and industries have faced painful disruptions due to the loss of market share due to increased competition, while others have benefited from the new market opportunities that have been created.