I can't help but snicker when people say that humanity is "killing the planet". You know what it takes to kill a planet? Asteroids. The size of Texas. If we piled every nuclear, biological, and otherwise unsavory weapon into one spot and set off the biggest fireworks display in the past 65 million years, I guarantee you that, 100 million years later, intelligent life would still be alive and kickin'. Would they be human? Probably not. But the point is that this planet is a tough old bird, and it's nothing short of arrogant to think we could take her down for the count. And that's not even taking religious beliefs into account.