I don't get it.

I decided - and we'll see how long this lasts - to read this year's Hugo and Retro-Hugo nominees for Best Novel. The Retro-Hugo, for those of you not following along at home, applies to novels first published in 1953. I've never had much interest in Golden Age SF - I bounced pretty hard off several books that are supposed to be classics, and eventually I gave up. But I'm eligible to vote for the Hugoes this year, and so I figured what the hell, I'll give the Golden Age another try.

So I read Arthur C. Clarke's Childhood's End, and I don't get it.
( here there be spoilers )