What will become of environmentalism in the future? Say we go to Mars and find that there really isn't any life there. Will the greens complain that we're disrupting the planet by building a colony on the empty red sand? Will they whine when we terraform that dead world and attempt to remake it in earth's image? And let's say we're successful in doing so... in fact, we colonize a dozen or so worlds in the next century or two. Will the greens then concede that earth itself has become expendable? There won't really be much need to conserve rainforests on earth if we plant one giant rainforest on some other planet, will there? Oh sure, it might look pretty to keep some parks around the old home planet, but it won't be essential will it? Accumulating trash won't be a problem anymore either once we can just toss it into the sun cheaply and efficiently, or convert it to nuclear power using the Mr. Fusion that satisfies all our energy needs.
One of the main problems I have with environmentalism is that I think it's just a charade. Environmentalists are intellectually dishonest. They proclaim doom and gloom, but their real agenda isn't to protect the earth, it's to hinder humanity. As Lileks writes today, the assertion that "IF EVERYONE LIVED LIKE YOU, WE WOULD NEED 6.9 PLANETS" makes me think hey, we'd better get started and find some more planets, so that all the poor, oppressed people in the world can live like me! The environmentalists, on the other hand, think that the solution is that I should start living like all the poor, oppressed people.
The environmentalist movement is the intellectual descendent of the Catholic Church of the Middle Ages. "The earth revolves around the sun?! Nonsense!" They routinely ignore and suppress the vast store of scientific knowledge that undermines their ideological dogma, and they villify anyone who stands up to them. This is unfortunate, because it's important to use our resources and environment responsibly and it's a shame that this message is tainted by the charlatans that hide behind it.