I plead ignorance about high finance, but I know enough (unlike some in Congress) that our financial system constitutes a sophisticated ”ecosystem” in which various elements interact. For the most part, this produces widespread wealth and prosperity.

As high gasoline prices and an election year fuel the need for scapegoats, some clumsy Congressional clods have been cursing speculators in futures and threatening to do something.

But futures serve a purpose.

Southwest Airlines paid $1.98 per gallon for jet fuel during the first quarter of 2008. The same fuel cost American Airlines $2.73, and United $2.83 per gallon during the same time period.

Southwest Airlines has been hedging fuel costs since 1999 – a practice which has saved the carrier $3.5 billion. At times the hedging has meant the difference between operating at a profit or a loss. In the first quarter of this year, the airline enjoyed hedging gains of $291 million.

Hedging is a strategy that allows a company to protect itself against rising prices for commodities, by locking in pre-set prices.

From trades it has made over the years, Southwest has managed to hedge 70 percent of its anticipated fuel requirements for 2008, at $51 per barrel rather than the current market price of over $140 per barrel.

“We view our program as insurance,” noted Paul Jacobson, Delta Air Lines Inc. treasurer. “Our goal is to minimize the volatility of fuel expenses. To do that, you’ve got to be in the market actively without an opinion as to what energy prices will do.”

Hedging carries risks, however. If fuel prices drop, airlines stand to lose money, and their options will expire.

Last week, news reports noted that “speculators” included such staid entities and teachers’ pension funds and the like. Better drag ‘em before Congress.

Rich Newman at US News shed some light with “6 Myths about Oil Speculators.”

So now we know who’s really responsible for $4 gas. Finger-pointers from Washington, the International Monetary Fund, and even Saudi Arabia no longer seem to buy the idea that the demand for oil around the world is simply growing faster than the supply, driving prices to record highs close to $140 per barrel. There must be a more nefarious reason, it seems. So now entering this drama is a villain everybody can hate: The Evil Speculator.

At recent congressional hearings, politicians and energy experts argued that speculators have artificially added $30 or more to the cost of a barrel of oil, turned oil trading into a global poker game, and doubled the price of gasoline practically overnight.

But who are these party crashers? Where did they come from? How are they doing this? And who can stop them? We’d all like to see a superhero swoop in and smite the speculators, saving Gotham from the peril of $4 gas. The only problem is, speculators aren’t quite the bogeymen that politicians want us to think—and they even play an important role in the oil markets and the global economy. Some major misconceptions:

Speculators are inherently bad for the economy. There’s no doubt that speculators are out to make money, by buying a commodity like oil (or gold, or real estate) when they think the price is likely to rise and they’ll be able to sell for a profit. But they also help sustain the market for buyers and sellers and provide ways for individuals and businesses to offset risks.

Many companies, for instance, want to lock in the price they’re going to pay down the road for petroleum products and other supplies they need to run their businesses. So they make agreements with suppliers on a price they’ll pay next year, or the year after, when they actually take possession of the oil. Buying and selling such “futures contracts” makes these companies speculators by definition, since they’re placing a bet on the future price of oil.

Companies doing this kind of hedging include gasoline refiners, airlines, shipping companies, and others that spend a lot on fuel or petroleum. Often they use investment banks or other intermediaries to arrange the deals. They might be gambling, but this kind of speculation actually helps companies run their businesses more smoothly, and if they guess right on future prices, it may give them a competitive advantage against other companies that don’t plan as prudently.

There‘s a Speculator Star Chamber somewhere. Global markets are so abstruse to ordinary folks that it’s easy to imagine a cabal of evil geniuses pulling the levers from some fortified complex in London or Geneva. But that’s the Hollywood version. “The market is so competitive that that’s nonsense,” says Bob Hodrick, a finance professor at Columbia Business School. “There’s no way for everyone to communicate and get together and say, ‘We’re going to buy and drive the price up.’ ” There are thousands of investors around the world placing bets every day on whether oil prices will go up or down—and they have no way of knowing who their fellow speculators are. All they know is the current price, shown on a computer monitor, plus whatever their own research tells them.