Final answer:
The United States joined NAFTA in 1993 primarily to eliminate tariffs and economically unite with Canada and Mexico, creating the world's largest trading bloc to compete globally. This agreement aimed to promote freer trade, stimulate economic growth, and reduce trade barriers in line with global free trade trends.
Step-by-step explanation:
The United States joined the North American Free Trade Agreement (NAFTA) in 1993 with several aims in mind. An essential motive for this economic partnership with Canada and Mexico was the elimination of tariffs and barriers to trade, promoting freer trade and investment flows. Therefore, the most accurate explanation for why the United States joined NAFTA would be that NAFTA eliminated tariffs and united the United States economically with its two closest neighbors. By creating the world's largest trading bloc, NAFTA aimed to enhance competitiveness against other global economic units, such as the European Union, and to stimulate economic growth within North America.
NAFTA effectively led to economic integration among the three nations, facilitating corporate investments across borders and causing shifts in industrial activity and migration patterns. While there was fear of job loss within the U.S. due to potential factory relocations to Mexico, where wages were lower, the broader goal was to foster an environment where goods could move freely among the participating countries, thus promoting economic prosperity on a larger scale. The ratification of NAFTA was primarily advocated by economists and aimed at reducing trade barriers, consistent with the global trend of promoting free trade among nations.