Commie, enviro. Watermelons. Green on the outside, red inside.
That UK Channel 4 documentary, I think, shows the correlation of the rise in radical environmentalism with the fall of the Berlin Wall and collapse of communism. All the crazies who hate the US/West and were sympathetic to the Commies joined the next "movement" and it just reinforces itself. Also take a look at the bio of a guy by the name of Maurice Strong (check wikipedia) -- he's really the guy behind all this, having worked the NGOs and the UN and the World Bank, etc. etc. to make a fortune off of these "movements" -- and he now has a leadership role (maybe CEO) of one of these carbon-offset companies that will benefit from all the eco guilt the stupid lefties in the US are displaying. It really is quite scary.
Michael Creighton also points out this correlation (fall of communism and the rise of extremist environmentalism) in his latest novel.
As for the Nazi's, a lot of crazies embraced that philosophy as well -- rationalizing that Hitler pulled Germany out of the depression faster than most countries... just another example of lefties seeking simple solutions through government power when the reality shows centralized government actions always fail in comparison with the free market.