Over the past three decades, the environmental movement has increasingly hitched its wagon to exactly one star as the overwhelming focus of the cause, namely "climate change." Sure, issues of bona fide pollution like smog and untreated sewage are still out there a little, but they are largely under control and don't really stir the emotions much any more. If you want fundraising in the billions rather than the thousands, you need a good end-of-days, sin-and-redemption scare. Human-caused global warming is your answer!
Even as this scare has advanced, a few lonely voices have warned that the radical environmentalists were taking the movement out onto a precarious limb. Isn't there a problem that there's no real evidence of impending climate disaster? But to no avail. Government funding to promote the warming scare has been lavish, and in the age of Obama has exploded. Backers of the alarm have controlled all of the relevant government bureaucracies, almost all of the scientific societies, and the access to funding and to publication for anyone who wants to have a career in the field. What could go wrong?