Too many of their opponents are intellectual thugs.
http://www.weeklystandard.com/articles/why-climate-skeptics-are-winning_631915.html
The forlorn and increasingly desperate climate campaign achieved a new level of ineptitude last week when what had looked like a minor embarrassment for one of its critics—the Chicago-based Heartland Institute—turned out to be a full-fledged catastrophe for itself. A moment’s reflection on the root of this episode points to why the climate campaign is out of (greenhouse) gas.
In an obvious attempt to inflict a symmetrical Climategate-style scandal on the skeptic community, someone representing himself as a Heartland Institute insider “leaked” internal documents for Heartland’s most recent board of directors meeting to a fringe environmental blog, along with a photocopy of a supposed Heartland “strategy memo” outlining a plan to disseminate a public school curriculum aimed at “dissuading teachers from teaching science.”