Does the concept of political correctness have any real meaning for a libertarian? After all, we advocate maximum freedom from state interference and believe in a “marketplace of ideas”. At least, I do.
Accordingly, all ideas will compete in this marketplace and opinions will vary in their distribution from those which nobody holds to those which are so widely held as to become hegemonic. If an opinion is noxious to me, I am free to refute it and to avoid association with the holder of that opinion if I wish. I am likewise free to attempt by peacable means to disadvantage the holder of the noxious opinion. As an example, I do not shop at Target to punish the company for its stance on dispensing emergency contraception. I do not support the Boy Scouts financially because I disagree with its position on homosexuals and atheists.
The real question seems to me to be when it should be considered unfair for a private individual to seek to disadvantage the holder of an unpopular opinion. For my part, I believe that it is in the best interests of humanity for popular, and especially hegemonic, beliefs to be problematized lest they become so entrenched as to result in a corruption of the idea market. Accordingly, one might seek to encourage the expression of ideas by committing to the principle that nobody should suffer any consequences solely on account of such expression.
But what kinds of ideas ought to be protected by believers in free expression? Certainly, the principle does not have unlimited application. In my view, it does not protect one from being a jackass by, for example, going to a church and proclaiming that Jesus did not exist, or posting pro-rape comments at a feminist blog, or carrying a “God hates fags” sign to a soldier’s burial. The principle does not pertain to violence or discrimination against people on the basis of phenotype or other hateful criteria. It does not pertain to statist or authoritarian views. It does not pertain to incitements to violence. It does not pertain to any ideas that are antithetical to free expression. It always pertains to ideas with which I happen to agree at the moment.
I suppose the range of ideas that would be protected by my principle of free expression is like obscenity in that I will know them when I see them.