Dear Mexican, Why do Mexicans call white people gringos? It was the type of impolite question few people would dare ask in everyday Southern California, much less in print. "Dear Gabacho," began Gustavo Arellano's answer in the OC Weekly alternative newspaper. "Mexicans do not call gringos gringos. Only gringos call gringos gringos. Mexicans call gringos gabachos." Arellano went on to explain that gabacho is a sometimes pejorative slang term for white Americans, with "its etymological roots in the Castilian slur for a French national." "Ask a Mexican," the newspaper headlined it. The column, published in 2004, was meant as a...