The European Free Market Trade Area published in 1957 served as a post war petition to bring economic unity to various European states previously in political opposition. Trade barriers prevent potentially valuable communications for solidifying positive social relations; historically, one country preventing the means of trade of another either served as a product of, or enabled political tension. Economic homogenization assisting as a method of political unification remained a common strategic political policy throughout the remainder of the century. The Maastricht treaty, the treaty on the European Union (1992), sought to aid in unifying Europe “through the strengthening of economic and social cohesion and through the establishment of economic and monetary union.” It also encouraged human rights reinforcements in the international sphere. European nations were not alone in promoting economic cohesion in the early 1990s, however. The Clinton Administration implemented the North American Free Trade Agreement (NAFTA) in 1994, which eliminated trade barriers between Canada, The United States, and Mexico, further stimulating trade between powerful North American nations, increasing solidarity. Nations seem to understand that economic inclusion is a powerful means to stimulate economies and maintain stability.