Well, naturally. But suppose that I make something and put it on a hidden page on my website (with a non-intuitive or random sub-URL), meta-tagged to repel searchbots, as a gift for my friends or people who do me a favor, like E-mailing me a response to my question, and one of those people posts a link to it so anyone can find it. It's not illegal by any stretch of the imagination, but it's certainly mean-spirited. Shouldn't I be able to ask people not to link to my content if I don't have the webtool-savvy to prevent it from happening, like Gamefaqs does?

A reasonable person contacts the host of the content, yes. People in general, however, are not reasonable. Remember those stories about the Secret Service threatening to shut down a spoof website because people posted links that would fill in the President's name in an obituary or "threatening" story? (Actually, in that case, the links were as much content as the stories themselves.) I'm still not trying to say that LJ is in the right or doing things the right way, but they are WITHIN their rights to demand that objectionable content not be linked, and we can pack up and leave or we can adjust and deal with it. Child porn was just an example that I threw out there as "the big issue" that everyone's focusing on. They talk about copyright issues sometimes, but everyone who's been named has posted or linked to content that was of questionable child porn status.