I don't think humans are going to be undone by self-destruction -- I think nature's going to take care of it. People never really look at how similar all living things are. And just like a human [or animal] body, I believe the planet has its own "immune system".
People say that the cause of all of the crazy weather [higher-level hurricanes happening more often, droughts, tsunamis..] is because we are polluting the planet -- but more specifically, it's the earth-body reacting to the things we do. I think it's going to do something large-scale to get rid of us, the "human disease".
There are lots of people who are talking about the Yellowstone SuperVolcano erupting [& quite possibly causing a chain-eruption of other volcanos in addition to tidal waves, toxic ash in the air, acid rain...] -- because of all of the activity that has been building in that area [small quakes are happening more frequently & with growing intensity]. I'm thinking that maybe it's like when we get sick and our bodies become feverish to burn out the "intruders".
This planet has been around far longer than any of us can even fathom. And the reason that it's stuck around is because it's strong and has ways of defending itself against threats. People always refer to the "end of the world", but the world isn't going to end -- we are. We humans like to elevate ourselves above all things, but in the end we are just animals who've been on the earth for less than 0.1% of its known existence -- and this planet has survived through the life & death of other "dominant" animal species [dinosaurs -- which were on this planet much longer than we've been, as well as a newly discovered reptilian species before them -- who knows how many more there have been?], and the planet always sorts itself out. It'll be able to not only survive, but thrive without us on it.
And in response to TexasDave's post[s]:
The environment isn't in God's hands [if you believe in that sort of thing] -- God gave us all free will; each of us is responsible for our own decisions & actions. We can choose to lead good, clean, peaceful lives in harmonic balance with each other & this planet -- or we can choose to live the highly destructive lifestyle of carbon-monoxide pumping cars, pointless wars, waste, pollution and general badness that we've chosen.
Also, the USA's twisted foreign policies [sanctions blocking nations who want to be "friends" with the USA from trading with Iraq -- which caused economic devastation & hundreds of thousands of deaths], general hypocrisy & corrupt ways is what drives many people to hate -- and terrorist groups to attack -- this country. And when you think about it, is the USA really any better than the terrorists as far as this war is concerned? Exponentially more innocent civilians are being killed [not to mention raped, beaten & tortured] than the so-called terrorists.. If it's all about the 3000+ lives taken on September 11th, I'd say we've gotten more than even with them for that, wouldn't you?
And as far as lots more people in 3rd world countries dying if we stop using fertilizers & insecticides -- that's a complete load of BS. The thing that most people don't even realize is that the vast majority of crops produced in this country go to feeding the animals that we eat! If even half of the factory-farm animals stopped being fed, every person in those countries would have enough to eat -- not to mention how much water would be saved [washing the pens & what the animals drink], and the large reduction in "run-off" pollution. That's one of the main reasons that people consider chemical-farming to be necessary -- fast food production to feed those animals raised for slaughter. If not for that, sustainable organic farming would be a highly viable option.
Sorry for the long post, folks.