> It's sort of a weird question to ask, anyway -- as if big
> social upheavals like this should or could be guided by
> some kind of instrumental rationality. Any upheaval is
> going to attract window-breakers.
Indeed. And it would be unfair for anyone to demand that OWS exclude or eliminate such manifestations. When the media or (worse) leftists proceed as if, magically, the movement had the obligation to exclude them from the getgo, I'm reminded of those who visit Venezuela and feign to be shocked that social inequality persists after ten years of Bolivarian revolution. But the fact that those things exist and have relatively deep roots does not require that we accept them or embrace them or apologize for them. They should not be blown out of proportion, but they are part of the problem.
> Seen in that light, the appearance of window-breakers is
> a sign of the Occupiers' success.
I agree. The success of OWS is likely to invite opposition from the powers that be, including those powers that stem from our own internalization of the status quo. In this regard, one of the most dangerous illusions is the notion -- inherent to certain forms of anarchism -- that to be individually free it suffices to act as if one were already free. However, if history shows anything is precisely that individual freedom is a joint or social product or is not, that we can only free ourselves through society. If individual freedom could be gained immediately outside of one's association with others, then all one would need is to go reside in the nearest jungle.
> Whether in fact they help or hinder the movement isn't
> actually so easy to answer -- though the answer clearly
> seems so self-evident to so many of us.
>
> As a general principle of method I would suggest that
> anything which seems self-evident is almost certainly
> wrong, and certainly deserves a closer look.
I guess it's always good to remind ourselves that in our social life things may not be as they appear at first sight. But it seems to me that what you are actually meaning to say is that the BB's actions, while apparently counterproductive, are actually for the good of the Occupy movement. I think that an outright argument in defense of the BB's actions in Oakland would help make this whole discussion more productive.