Conversation so far:
What was the Toby Keith Dixie Chicks feud regarding?
Toby Keith had a feud with the Dixie Chicks over the song Courtesy of the Red, White, & Blue.
Was the Toby Keith Dixie Chicks feud about anything else besides the song Courtesy of the Red, White, & Blue?
Toby Keith had a feud with the Dixie Chicks over the latter's comments about President George W. Bush.
What did the Dixie Chicks say about Toby Keith?
The lead singer of the Dixie Chicks, Natalie Maines, publicly stated that Courtesy of the Red, White and Blue was ignorant, and it makes country music sound ignorant.

Question: How did Toby respond?
Self-contained rewrite: How did Toby Keith respond to the Dixie Chicks' comments directed at him?