ABOUT 8.5 million cars and light trucks were assembled in the United States last year, but only about five million of those were made by the automakers traditionally known as the Big Three. More than three million of the vehicles assembled in American plants were built by autoworkers employed by foreign brands like BMW, Honda, Hyundai, Mercedes-Benz and Toyota.

Add to those the familiar Detroit nameplates coming from plants in Canada and Mexico and it’s easy to see how confusing it can be for consumers leaning toward the purchase of an “American” car. Which is the more American product, a Honda Accord built by Ohioans for a company with its headquarters in Japan, or a Ford Fusion built in Mexico for a corporation that is based in Michigan?

Among the so-called transplants  foreign automakers who produce vehicles in the United States  Toyota leads in production. Last year it built more vehicles in the United States than Chrysler, although the margin was small  only about 11,000 vehicles. Honda was the first Japanese automaker to start building vehicles in the United States when its Accords began rolling off the assembly line in Marysville, Ohio, in 1982. In the ’80s and ’90s the Big Three began building more vehicles in Canada and Mexico.

Of course the window sticker of a new vehicle lists its domestic content, including the origin of its engine and transmission, but the intricacies of the North American Free Trade Act and the American Automobile Labeling Act can muddle details on parts from Canada and Mexico.