Taco USA.

The author of "Ask a Mexican," Gustavo Arellano, is out with a new book that explores tacos and their conquering of America. In it, Arellano chronicles how multiple culinary traditions collided to create the bagged tortilla chip, the chicken fajita, the frozen margarita, and countless other staples of the contemporary American diet. Some of his conclusions and observations are eye-opening. So raise a margarita and salute the multi-cultural preeminence of Nuevo Cuisine!