Lance Mannion, the voice of reasonableness, explains why liberals need to be unreasonable sometimes:
I don’t know why six religious nuts are allowed to ruin a holiday for a hundred kids. I don’t know why a relatively small pack of paranoid racists and Right Wing extremists are allowed to prevent everybody’s else’s kids from hearing the President of the United States advise them to work hard and stay in school. But I suspect that part of the reason is that sensible parents who may get mad don’t stay mad. They have other more important things to worry about and they move on to worry about them. The Right Wing nuts get mad, stay mad, and don’t let up. School officials who ignore the complaints of sensible parents know that by the end of the semester the sensible parents will have forgotten about the issue; but the nuts won’t forget, won’t drop it, and won’t let up—run into them anywhere, anytime and they’ll start screaming all over again. It’s just easier and it moves the problem off the desk more quickly to cave to the nuts, knowing you probably won’t hear a peep from the sensible parents.
As the old saying notes, it’s the squeeky wheel that gets the grease and the same goes for political change. You need people to either be afraid of you or think that it’s easier for them to give in to you than to resist you. Yes, this can backfire, but surprisingly less so than is commonly assumed. All great change happened through radicalism, civil disobedience and a refusal to be reasonable.
In a roundabout way, this is also why you don’t want to debate the BNP as much, as to make it socially unacceptable to support them. You can’t argue racist fuckwits into not being racist, you can scare them into not being openly racist.