There is no shortage of billionaires -- the Koch brothers, Carl Icahn, Dan Loeb and, yes, Mike Bloomberg, to name a handful -- who are willing to use their vast wealth to push a particular political agenda or to advocate for a specific social reform. That’s hardly a revelation.
Bill McKibben published The End of Nature in 1989, one of the first popular books to explain global warming. In recent years, he has turned to climate change activism, founding 350.org in 2008 with seven undergraduate students to build "a global grassroots movement to solve the climate crisis," according to its website. The group now has about 50 employees and works with voluntary organizers in approximately 190 countries. McKibben is one of the most visible activists fighting the construction of the Keystone XL pipeline, which would deliver Canadian oil sands crude into the U.S., if approved by the Obama administration.