Congress is doing the right thing in moving toward some restrictions and more government oversight of the oil futures markets. Earlier this week, the Senate passed legislation designed to rein in rampant oil speculation.

While some action is warranted, it is important that government not stifle, or drive offshore, the futures markets. Futures contracts for commodities, including grains, metals and oil, serve important business purposes. Southwest Airlines, for example, has had success in buying oil futures that locked in moderate prices while some of its competitors were buying higher-priced fuel on the open market.

But unlike Southwest, there are other speculators who never take possession of the oil — they simply are making a bet that oil prices will rise. And when enough of these pure speculators make that bet, they can create a self-fulfilling prophecy that makes them big profits.

Ultimately, the speculative bubble surrounding oil, like other speculative bubbles, can or will burst. But until then, speculators' bets are believed to be adding $30 to $60 a barrel to the price of oil. And those big profits being made by speculators are costing millions of Americans at the pump.

To more than a few critics of oil speculators, it looks like the Wall Street greed that drove speculation in dot-com stocks in the 1990s and then subprime mortgages over the past few years has now turned its attention to the big profits to be made in oil speculation.

No one should believe that speculators are entirely to blame for the skyrocketing price of oil. Imbalances between global supply and demand, driven in part by the rapidly expanding economies of China and India, probably are mostly to blame for today's high oil prices.

Despite disagreement over the extent of the impact that speculators have on oil and gasoline prices, there is no doubt that activity in oil speculation has exploded recently.

For decades, speculators were thought to represent only about 21 percent of the oil futures markets. Six or seven years ago, it was estimated that about 37 percent of those buying oil futures were speculators. Now, however, speculators reportedly account for 65 percent to 70 percent of the market.

This has to be having an effect on oil prices. Rampant speculation contributes to increased volatility and also tends to drive up prices.

One proposal being considered in Congress would increase the margin requirements — that is, money that has to be put up to enter into a futures contract, for those who are pure speculators. Lower margin requirements would remain for those futures contract buyers who also had a legitimate interest or business need for locking in oil prices — such as airlines or oil refineries.

In fact, a letter supporting more government involvement and oversight of the oil futures markets has been signed by the chief executives of 12 major U.S. airline companies, including Southwest Airlines.

The Pennsylvania Petroleum Marketers & Convenience Store Association also backs the Senate bill to curtail speculators' impact on oil prices.

Consumers are feeling the pain of higher oil prices, and most airline companies are struggling to survive in the face of fuel costs that have more than doubled in the past year.

Reining in oil speculators is not the only answer to bringing down oil prices. Reducing demand while increasing supply — and developing renewable alternatives — will be required, but there is clear evidence that cooling off some of the speculation is warranted.