<P> The Canada--United States Free Trade Agreement laid the groundwork for a multilateral and multicultural agreement between, the United States, Mexico, and Canada, called the North American Free Trade Agreement (NAFTA), which has helped to increase more trade among them . Although there are some dysfunction between the countries' especially in the area of automobiles and agriculture, the trends are negligible as the agreement has arguably been a boon for all nations involved . </P> <P> There are several disputes arising from the bilateral trade between the two nations . The United States placed Canada on its Special 301 Report intellectual property rights enforcement (although under the mildest category of "rebuke"). Other products from Canada under dispute include softwood lumber, beef, tomatoes, and other agricultural products . </P> <P> The heightened border security as a result of the 2001 terrorist attacks has been an issue of concern for businesses in both countries . The issue has become less of a concern since the attacks with the development of new technology, registration, training, and fewer rules . However, a midpoint estimate of US $10.5 billion cost to businesses in delays and uncertain travel time have affected trade . </P> <P> One ongoing and complex trade issue involves the importation of cheaper prescription drugs from Canada to the United States . Due to the Canadian government's price controls as part of their Single - payer medical system, prices for prescription drugs can be a fraction of the price paid by consumers in the unregulated U.S. market . While laws in the United States have been passed at the national level against such sales, specific state and local governments have passed their own legislation to allow the trade to continue . American drug companies--often supporters of political campaigns--have obviously come out against the practice . </P>

Where are manufacturing and trade concentrated in the united states and canada why might this be so