Everyone who's filled up on gas recently got a sticker shock on seeing how fast the price went up after Katrina. When the Gulf's production was shut down, there were 2 million less barrels available to the US every day.
The bigger problem is that the world's oil supply is stretched to its limit right now, with no excess production. Any disruption like a hurricane is enough to send prices zooming.
About a year ago I became interested in the problem of oil and did some reading about it. If you do a search for "Hubbert's peak" you'll find many websites about it. Many good geologists are saying that the world is almost at the point of peak oil--when we will have used half of all the world's easy-t0-get oil. There will still be a lot left, but the supply will be shrinking. Demand goes up all the time, so the price will, too.
Some of the out-of-oil scenarios are scary and perhaps too alarmist. But there is a real problem and the sooner we start to conserve oil and develop alternate energy sources, the better. Oil burned is gone forever and it takes the earth millions of years to produce it. In about 125 years we've used up half of all the oil--what about people in the centuries to come?