By legitimizing bigotry and redefining so-called American values, a revived Klan in the 1920s left a toxic legacy that demands reexamination today. "A new Ku Klux Klan arose in the early 1920s, a less violent but equally virulent descendant of the relatively small, terrorist Klan of the 1870s. Unknown to most Americans today, this 'second Klan' largely flourished above the Mason-Dixon Line--its army of four-to-six-million members spanning the continent...