The "threat" of drilling lowers the price of gas at the pump. Look what has happened over the past two weeks. A natural disaster has no effect on the availability of oil or refining for months, but the price skyrockets within hours. It will be decades before a renewable energy source is affordable and available for widespread use, until then our economy depends on the lowering the cost at the pump. The available alternate energy sources currently available (ethanol) aren't that practical, and now you are seeing a jump in the price of food because of the attempt to use corn to boost the production of ehthanol. Add to that, ethanol doesn't really do too well when you try and pipe it places.
I hate to say it, but that bimbo paris has a good point.