The Chicks were the preeminent country group of their generation, transforming the sound and sensibility of the genre at the dawn of the 2000s with their multi-platinum albums Wide Open Spaces, Fly, and Home. Steeped in country tradition -- in their earliest incarnation anchored by Emily Strayer and Martie Maguire, they were a western outfit, singing songs by Texan troubadours -- the Chicks were transformed when Natalie Maines joined the band in 1995. Maines brought a steely defiance and an unorthodox pop/rock sensibility to their music, characteristics that were evident on 19...