Thanks, PiratePrincess and kate1956, and not a sarcastic thanks, either, as I realise I should be more nuanced in my belief in free speech.
Of course I don't believe in promoting hate speech, but I also think that racist/extremist parties such as the BNP benefit from too great a degree of censorship. If information by them and about them is confined to margins and "channels" which people have to seek out, they will not be subject to mainstream scrutiny, and will be able to hide better.
Of course, there is a danger of normalising and legitimising extremists and extremist views, so we should be careful not to guarantee political "balance" (though, given the nature of the UK's media, no chance of that!).
There is also a danger that extremists will "raise their game": that is, subjected to more rigorous scrutiny, they will sharpen their intellectual skills and begin to sound more "reasonable". I suppose that could mean a temptation to cut off unpleasant views from the resources to improve their intellectual position, whether those resources are universities or media.
Hmm.... that last line of thought keeps going, and I will have to think to the end of it.
However, another thing to do is to raise the standard of debate and scrutiny by and on behalf of views which are humane and just. There is an appalling laziness about political discourse in this country. DH and I were discussing politics last night, and we decided that part of the reason for this is the stupid lack of proportional representation, which means parties target their efforts on marginals, rather than fighting a really broad and meaningful campaign about what they really believe in. Meanwhile, media understanding also falls short, with this obsession with the "swing", as though we only have two political parties. That's not quite true, is it?
If major political parties are failing to say what they mean, because they can rely on voters' gut feelings, aren't they benefiting from the same censorship I was talking about above, which benefits unpleasant extremists like the BNP?
I'm just making this up at the moment, so please do consider it a real debate and attack these ideas with proper rigour - otherwise, I'd be a bit of hypocrite!