It's hardly a stampede. But as Zack Roth has reported over recent days, a non-trivial number of major American corporations have now either cancelled their membership in the US Chamber of Commerce (Apple), resigned from the organization's board (Nike) or explicitly dissociated itself from the Chamber's position on Global Warming (GE). The names include Nike, GE, several major regional utilities and now Apple.

It's still only a handful, of course. But it's an interesting illustration of the different dynamics of the global warming issue than say health care or other regulatory policy issues or labor relations -- particularly for companies in the energy field and those involved in mass consumer marketing.

It's not hard for instance to understand why a company like Nike, which markets overwhelmingly to a younger demographic and to some degree is in the business of marketing cool, would not like to be associated with anti-climate change science extremism. Similar things could be said about Apple, which markets to generally wealthier, more educated and I suspect -- though I don't know this specifically -- generally more progressive people.

There's simply mass awareness and politicization on this issue in a way there's not about most high stakes political questions. I also wonder whether some companies may not be sensitive to the impact on their reputation on an international trade, those doing a substantial amount of international trade. But the mass politicization and company's sensitivity to domestic brand damage strikes me as the key takeaway for now.