Bigotry never goes away. When it becomes unfashionable, it goes underground and waits until a new hate group appears into which it can project its twisted sickness. Racism, anti-Semitism, anti-Catholicism and anti-immigrant nativism are chronic infections in the American body politic. Rush Limbaugh singing his obscene tune "Barack the Magic Negro" is inviting prejudice and violence. However, for pure irrational rage, the current crop of nativists are some of the worst to come along since the Ku Klux Klan of the 1920s or those God-fearing Protestants who burned convents in Boston in the 19th century.