Excellent post from Gaiman on the reason he's so supportive of anti-censorship movements. He's long supported the CBLDF and often speaks of the need to be ever vigilant on these matters. But a recent letter asking how it's possible to defend Lolicon especially in Manga triggered a long essay on the subject.
Towards the end is a great quote, that sums up everything the post is saying:
Because if you don't stand up for the stuff you don't like, when they come for the stuff you do like, you've already lost.