Charles Brown has, I think, given the best statements of the perspective for banning hate speech. I think, in essence he is arguing for such as a positive reform that is positive, even if carried out in a capitalist, racists, sexists society -- and in this aspect comparable to trade unionism, or socialized health insurance, and other such reforms.
The practical difference I is that while the other reforms are positive even when contaminated and distorted by various oppressions, controls on speech are not. For example, if the U.S. (the only rich country relying primarily on private insurance to pay for health care) were to adapt single payer health this would be positive for everyone, including the poorest of the poor, non-whites, women. The fact that the medical profession is still overwhelmingly white and male , that rich areas have better and more hospitals and doctors than poor, the oppression of the disabled and the old, the thousand and one types of structural unfairness that would remain in our medical system would not keep it from being a tremendous improvement. (Of course in winning single payer health,we would try to build in precautions against these evils. And after it is won, we would continue the struggle.) But even as poorly implemented as systems as Canada's, with health care reduced to provide property tax cuts, is immensely superior to the mess we have in the U.S.
Compare to this to censorship of hate speech -- group libel laws , let's say or any of a thousand other types of proposal. In a capitalist society could you pass a group libel law that does not include "hate" speech against white people, men, heterosexuals, rich people, and christians? Don't you think some way would be found to distort them to stop far more left wing speech than right. What you would inevitably end up with is a law that was "equally" applied to ban the KKK and Nazis on the one hand, and Brad De Long on the other (with anyone to the left of Brad automatically going to jail). The point is an imperfectly implemented single payer plan is a lesser good. An imperfectly implemented hate speech law is a weapon of oppression against the entire left. I would add that since I know no perfect leftists, this would be an excellent practical argument against censorship in a left wing society. There are a number of people on this list I admire -- but I cannot think of any of them I would trust to tell me what I could or could not say. For that matter I don't think I would trust myself with the job of censoring others.
Now another point: Carrol discussed Locke as a tremendous advance in political thought. Now Locke did indeed make a number of tremendous advances in political thought. And the social compact is indeed a radical advance -- in fact more radical than is usually realized. But the idea of the social compact (not contract) was invented not by Locke, but by Hobbes -- who in spite of immensely conservative leanings was the inventor of modern liberalism.
You see, the idea of the social contract was not new, but went back to at least mediaeval times and probably to before Aristotle. The idea that government represents an agreement, a promise between ruled and ruler is an advance over simple divine right. Under the social contract idea, rulers at least have some obligation to the ruled. But idea of a social compact was far more radical. For the idea of a social *compact* is that each agrees with the other to obey the state, the great monster. In short under the social compact theory the people owe *nothing* to any ruler. Their obligation is to one another. Government is no longer a sacred obligation, but a mere instrument, a tool of the ruled.
Now Hobbes was not an idiot. Many people have suggested that he aware at least some of the implications of what he was writing. Cromwell was firmly in command at the time Leviathan was published. By staying on the abstract plane, it could be taken both as a defense of the old monarchy, and as a defense of the new dictatorship -- since any power that people obey could be considered legitimate under this idea.
Lockes brilliance (in addition to a great many important specifics) was in seeing more of the implications of this idea. If you read Locke, though he uses the term "contract" rather than "compact" you will find almost the exact same wording as Hobbes -- that each agree with ever other. You can also find it in Rousseau. But Locke deserves the credit for truly seeing the revolutionary implications in what was intended to be a conservative document. Note you have to see both tendencies here; the reactionary tendency is inextricably woven with the progressive one. The absolute right of revolution is there in dialectical tension with the absolute right of any government which is obeyed to be obeyed.
Still in this highly deductive, and postulate driven political philosophy, you have the first hint, just a small taste of the government not only subordinate to the people, but shaped by social circumstance.
It also is an idea shaped by material conditions. Only in a world where new instruments were being developed at at the astounding rate of many dozens per century (not irony -- truly an acceleration compared to the past) could the idea of government as a mere instrument itself occur.
-- Gar W. Lipow 815 Dundee RD NW Olympia, WA 98502