I read that book by Mackay this weekend, very informative, thanks for posting it. I think a lot of his policy suggestions are questionable because he tends to ignore the question of cost, but he's definitely on the right track by doing an actual cost-benefit analysis, it's kind of sad how rare that is.

Most of the environmental debate is on the level of this editorial from the WSJ yesterday, where they just cite one negative effect of something and throw out some huge-sounding numbers to make it sound really important.