The political gap was particularly large in terms of views on free trade with Mexico. Contrary to a positive view of free trade with Canada, which 79% of Americans called fair trade partners, only 47% of Americans thought that Mexico practiced fair trade. The gap between Democrats and Republicans has widened: 60% of Democrats thought Mexico was fair trade, while only 28% of Republicans did. That was the highest number of Democrats and the lowest figure ever recorded by Republicans in the Chicago Council survey. Republicans had more negative views on Canada than fair trade partners and Democrats.  Shortly after his election, U.S. President Donald Trump said he would begin renegotiating NAFTA terms to resolve trade issues for which he had campaigned. The heads of state and government of Canada and Mexico have expressed their willingness to cooperate with the Trump administration.  Although he vaguely formulated the precise terms he wants in a renegotiated NAFTA, Trump has threatened to withdraw from it if negotiations fail.  If the original Trans-Pacific Partnership (TPP) were to enter into force, existing agreements, such as NAFTA, would be reduced to provisions that do not conflict with the TPP or require greater trade liberalization than the TPP. However, only Canada and Mexico would have the prospect of becoming members of the TPP after U.S. President Donald Trump withdrew the United States from the agreement in January 2017. In May 2017, the remaining 11 members of the TPP, including Canada and Mexico, agreed to pursue a revised version of the trade agreement without U.S. participation.  According to a study published in the Journal of International Economics, nafta reduced pollution in manufacturing in the United States: « On average, nearly two-thirds of reductions in emissions of coarse particulate matter (PM10) and sulphur dioxide (SO2) from U.S. manufacturing between 1994 and 1998 can be attributed to trade liberalization to NAFTA. »  These agreements between three or more countries are the most difficult to negotiate. The larger the number of participants, the more difficult the negotiations. They are, by nature, more complex than bilateral agreements, insofar as each country has its own needs and requirements.
The North American Free Trade Agreement (NAFTA) was implemented to promote trade between the United States, Canada and Mexico. The agreement, which removed most tariffs on trade between the three countries, came into force on 1 January 1994. Between 1 January 1994 and 1 January 2008, many tariffs – notably for agriculture, textiles and automobiles – were phased out. Congress approved the negotiations in 1984 and Canada-U.S. The free trade agreement was concluded in 1988. When Mexico, to everyone`s surprise, wanted a similar agreement, the result was the North American Free Trade Agreement (NAFTA) with three nations. This proved to be the most controversial of all U.S. trade agreements, in part because average wages in Mexico were only a fraction of U.S. wages, giving Mexicans an advantage over labour-intensive products, threatening U.S. employment. After a Herculean struggle, the Clinton administration won congressional approval in 1993.
Promote the conditions for fair competition in the free trade area. A 2007 study showed that nafta had « a significant impact on the volume of international trade, but a modest impact on prices and prosperity. »  In the first two decades of the agreement, regional trade increased from about $290 billion in 1993 to more than $1 trillion in 2016. Critics are divided on the net impact on the U.S. economy, but some estimates put the net loss of domestic jobs at $15,000 a year as a result of the agreement. , such as rules of origin and documentation obligations, which determine whether certain goods are