That doesn't seem like a very accurate paraphrase of what Miles is saying, or what I've read from Carrol many times on this list. I don't think they're saying that movements "just happen"; more the opposite, really. Miles's point that moral positions are products of, rather than causes of, social conditions, doesn't mean that moral beliefs are simply objective factors beyond our control. Rather, the point is, that if we want to change people's behavior (and thereby their moral positions), we shouldn't do it by attempting to persuade them, but rather by attempting to change social conditions.
This doesn't imply any kind of fatalism or quietism, which you seem to attribute to Carrol. Actually, it implies the opposite. If moral persuasion is a pre-condition of political organization, we will have to wait until people agree with us before beginning to organize. Carrol's position, on the other hand, advocates beginning to organize now, in order to induce more people to agree with us in the future.
--
"The slightly richer ... eat in semi-darkness, preferring
candles to electricity. These candles make me laugh. All the
electricity belongs to the bourgeoisie, yet they eat by
candle-end. They have an unconscious fear of their own
electricity. They are embarrassed, like the sorcerer who has
called up spirits he is unable to control."
-- Vladimir Mayakovsky http://blog.voyou.org/ voyou at voyou.org