I've heard a lot of mindless chatter from both sides of the issue. The truth is like a game of chess: both simpler and more complicated than either side of the issue would care to admit.
Let's forget about our religious beliefs for a while. The evidence shows that the earth is about 4.5 billion years old. It has endured warming trends much more pronounced than the current one several times in its long history. A few hundred million years ago, long before us humans had even arrived, one such trend apparently killed almost every living being on the surface of the earth. The entire surface of the earth became a lifeless desert. Luckily, the oceans didn't boil away, or we wouldn't be here today. Likewise, it endured an ice age in which the entire earth was covered in thousands of feet of ice for hundreds of millions of years. We aren't anywhere near either of those extremes right now.
We like to think of ourselves as all-powerful, but natural events can change the climate far more than our species can. An eruption of a single megavolcano or an asteroid strike can do far more to change the environment in an instant than the entire human race has done in the past 10,000 years. Climate change is a given, as is the extinction of species of animals who can't compete effectively or survive changes to their environment. Our planet was constantly changing before the human race began, and will continue changing whether we as a species survive or not. It survived the extinction of the dinosaurs, and it can survive without lions, tigers, or even us humans, if we are stupid enough to kill ourselves off as a species. Reality bites. Nature is a cruel mistress.
But that doesn't let us off the hook entirely. While we probably haven't doomed the planet by our pollution, it has had some effects. For the past several million years, there has been a cycle of an ice age which lasts about 100,000 years, then a short warming period lasting a few thousand years, then another ice age. We may either be prolonging the current warming period, or shortening it. We just don't have enough real information to know which. There do seem to be some triggers which stop the earth from becoming a lifeless hothouse like Venus, the victim of a runaway greenhouse effect, or Mars, which is at the other extreme, its atmosphere gone and its oceans frozen underground. Our deep oceans, the ozone layer in the atmosphere and the trade winds seem to shift the balance back in the other direction whenever the earth gets too hot or too cold. Whether we opt for a greener future or not, our descendants won't inherit a planet that looks like the Earth of today, but the human race has always been able to adapt and survive. In the human race's 3 million years, it has endured literally dozens of ice ages before, and those were without the technology we have today.
We do have some really valid reasons to "go green" that will affect us and our children, not some generation so far in the future that it's past our comprehension, though. Let's look at the facts. The U.S., Russia and Saudi Arabia were all producing about 8-10 million barrels of oil per day 30 years ago. Our own production has declined by over half. Russia's has declined a little, but its government claims that its supplies will begin running out by 2020. S.A., on the other hand, claims to have enough oil to step up their production to 20 million barrels per day, and keep that level up for the next 200 years. Something tells me that they're lying through their teeth. If they really had that much oil, they wouldn't be spending tens of billions of dollars buying speicalized equipment to get the last drop out of declining oil fields. They wouldn't have had to use oil from storage to step up production last spring. They would be setting up new oil fields instead of trying to get the last few barrels out of their three top producing fields. They wouldn't be attempting to wean their economy off of the oil riches and investing heavily in so many other industries. In other words, the world is running out of oil. That fact alone will solve a lot of the pollution problem, but it is also likely to turn us into a third-rate country if we remain addicted to foreign oil. We saw the devastating effects of a temporary upturn in the price of gasoline this past year. People had to decide whether to buy gas or pay their bills, whether to buy gas or groceries, to buy gas or save for those big Christmas presents. Gas won, people couldn't afford to buy gas and pay for their houses, buy new cars or buy anything from a hamburger to a washing machine, and the entire economy toppled into a deep recession. Just imagine what would happen if that huge jump in energy prices had become permanent. It is imperative to our security, and even our survival as a nation, that we secure our own energy supplies, something cheap, renewable and domestic.