It is not mysterious why conservatives think the Phil Robertson disciplining is rights-infringing but think the Dixie Chicks disciplining was not. They support what Phil Robertson had to say, but oppose what the Dixie Chicks had to say. Despite their pretensions to the contrary, conservatives, and most people in general for that matter, do not care about content-neutral procedural fairness. They care about winning their stuff and beating the other’s side stuff.
…Most of the time, proclaimed commitments to uncoerced free speech, minority parliamentary power, states rights and any other content-neutral procedural rule are not serious. Some people are seriously concerned about process for its own sake, but such people are few and far between. Everyone else has a substantive agenda and merely stakes out the short-term positions on content-neutral procedural justice that further that agenda. Filibusters are good when they block what I dislike, but bad when they block what I like. States rights are good when states do what I like, but bad when they do what I dislike. Private economic coercion of expression is good when it shuts down comments I dislike, but bad when it shuts down comments I like. And so on.