Ready for $100-a-barrel oil? Despite a recent stall in oil's steep price climb, that symbolic milestone could be here by Thanksgiving. So what can we do to reverse the surge in prices, or at least soften its impact? Not much.

Americans are wincing every time they fill up their cars' tanks. They should at least understand what's driving prices to such levels.

To start, forget the usual suspects — the mess in Iraq or oil shortages. Instead, look first at traders in the futures markets of New York, London and Tokyo, where oil is just another commodity. When the subprime mortgage markets imploded, big investors looked elsewhere to find profit. They found it in oil. Not only did they see soaring demand in China and India, which more than make up for a drop in U.S. consumption. They also heard rumblings of war with Iran. And there's nothing better than war with a major oil producer — or even rumors of war — to excite the futures markets.

Even the sharp cuts in interest rates by the Federal Reserve boosted oil prices. They lowered the dollar's value, and since oil prices are tied to the dollar, producers had to jack them up to keep profits steady.

Driven by market speculation, the current oil price bubble could burst, just as the housing bubble did.

For our part, Americans should consider parking their big SUVs and driving fuel-sipping compacts while dialing down the thermostat. It won't change oil prices immediately, but it will cut costs.