Jeffrey Davidow coined the phrase "the bear and the porcupine"--which has now entered Mexican political discourse--to describe the difficult relationship between the hypersensitive Mexican "porcupine" and the "insensitive" American bear. In this revised and expanded second edition, Davidow picks up the story of U.S.-Mexican relations since he left his ambassadorial post in 2003, explaining the implications of the Fox administration and the outcome of the 2006 election and reflecting on the volatile immigration issue that has exploded into public debate in the United States.