Jamais Cascio writes a very interesting article about the role of environmentalism. He clearly points out the pointlessness of the "save the planet" meme. Environmentalism should really be focusing on trying to preserve human civilisation, not the Earth and the current state of its ecosystems. As he accurately puts it: "The grand myth of environmentalism is that it's all about saving the Earth. It's not. The Earth will be just fine. Environmentalism is all about saving ourselves."
Of course preserving ecosystems and the availability of clean water supplies, topsoil, etc. is of the utmost importance. Preserving the environment in order to support human activity on the planet, ie. sustainable living should be our greatest concern. "Human civilization could not withstand and recover from the same kinds of assaults the planet itself has shrugged off in eons past. We remain entirely dependent upon myriad Earth services and systems, from topsoil and clean water to carbon cycles and biodiversity. Activities that undermine those critical services and systems quite literally threaten the survival of human civilization."