The OBJECTIVE of NAFTA was to remove barriers to trade and investment between the United States, Canada and Mexico. The implementation of NAFTA on January 1, 1994 resulted in the immediate removal of tariffs on more than half of Mexican exports to the United States and more than one-third of U.S. exports to Mexico. Within 10 years of the implementation of the agreement, all U.S.-Mexico tariffs should be eliminated, with the exception of some U.S. agricultural exports to Mexico, which are expected to expire within 15 years.  Most of the trade between the United States and Canada was already duty-free. NAFTA also aimed to remove non-tariff barriers and protect intellectual property rights on marketed products. A “secondary agreement” reached in August 1993 on the application of existing domestic labour law, the North American Convention on Labour Cooperation (NAALC) , was severely restricted. With regard to health and safety standards and child labour law, it excluded collective bargaining issues, and its “control teeth” were only accessible at the end of a “long and painful” dispute.  The obligations to enforce existing labour law have also raised questions of democratic practice.  The Canadian anti-NAFTA coalition Pro-Canada Network suggested that guarantees of minimum standards in the absence of “extensive democratic reforms in the [Mexican] courts, unions and government” would be of no use.  However, subsequent evaluations indicated that NAALC`s principles and complaint mechanisms “created a new space for princes to form coalitions and take concrete steps to articulate the challenges of the status quo and promote the interests of workers.”  Clinton signed it on December 8, 1993.
The agreement came into force on 1 January 1994.   At the signing ceremony, Clinton paid tribute to four people for their efforts to reach the historic trade agreement: Vice President Al Gore, Council of Economic Advisers Chair Laura Tyson, National Economic Council Director Robert Rubin and Republican Congressman David Dreier.  Clinton also said, “NAFTA means jobs. U.S. jobs and well-paying American jobs. If I didn`t believe it, I wouldn`t support this agreement.  NAFTA replaced the old Canada-U.S. free trade agreement. Nevertheless, there is something great about this confusion between NAFTA and the letters of globalization. The agreement “launched a new generation of trade agreements in the Western Hemisphere and other parts of the world,” the CRS writes, so NAFTA has rightly become an acronym for 20 years of broad diplomatic, political and trade consensus that free trade is generally a good thing. The kick-off of a North American free trade area began with U.S. President Ronald Reagan, who made the idea part of his 1980 presidential campaign.
After the signing of the Canada-U.S. Free Trade Agreement in 1988, the governments of U.S. President George H.W. Bush, Mexican President Carlos Salinas de Gortari and Canadian Prime Minister Brian Mulroney agreed to negotiate nafta. Both submitted the agreement for ratification in their respective capitals in December 1992, but NAFTA faced considerable opposition in both the United States and Canada. The three countries ratified NAFTA in 1993 following the addition of two related agreements, the North American Worker Cooperation Agreement (NAALC) and the North American Environmental Cooperation Agreement (NAAEC). The USMCA contains a “Sunset” clause – the terms of the agreement automatically expire after 16 years, unless they are expressly renewed by the parties. Originally, the United States wanted a five-year sunset clause.
According to a 2013 Jeff Faux article published by the Economic Policy Institute, California, Texas, Michigan and other high-concentration manufacturing states were most affected by NAFTA job losses.  According to an article by EPI economist Robert Scott