Almost 140 miles off the Louisiana coast, aboard the drill ship Noble Paul Romano, workers punch an 8-inch steel pipe four miles under the ocean in search of America's next barrel of oil.

"If we don't increase our own oil production in the U.S., our dependence on foreign oil won't go down," said Marathon Oil executive Woody Pace.

The drill ship is the size of a football field. Twelve anchors the size of an average living room hold the rig in place while a synthetic-diamond cutting blade bores deep into sand and rock.

Like other oil explorers, Marathon is being forced farther and farther out into the Gulf to find oil. Deeper water means more expensive oil.

"We may spend anywhere from $100 to $200 million just to find out if we have commercial hydrocarbons," Marathon Vice President Annell Bay told FOX News.

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Marathon is a Houston-based oil company than not only explores for oil and natural gas, but refines oil as well.

Marathon dumped $230 million into developing the Droshky oil field, which it acquired in 2007, but expects to spend more than $1.3 billion when it begins pumping next year, about the time the economy is expected to recover.

And while every drop counts, many fear it won't be enough.

"We all have hope for green energy, but it is going to take time — and in the meantime, oil and natural gas will have to be the bridge to the energy future," says Cathy Landry, a spokeswoman for the American Petroleum Institute.

Congress lifted its 27-year moratorium on drilling off Florida and the East and West Coast last year, but billions of barrels of that oil remains untouched and off-limits because the Obama administration has postponed development there.

The Obama administration favors green energy and provides generous tax subsidies to wind and solar. By contrast, this week the oil industry complained that Obama proposed hiking their taxes by $70 billion over 5 years, including a $122 million on leases the administration considers non-producing.

"If you penalize oil and gas, and add taxes, it is going to make it much more difficult and more expensive. That means U.S. jobs are exported and we won't get the revenues from royalties," said Landry.

Oil executives fear the lesson of $5-a-gallon gasoline is lost, and that American consumers will pay the price, vulnerable to shortages in the short term and a continued dependence on foreign oil for decades to come.

William La Jeunesse joined FOX News Channel (FNC) in March 1998 and currently serves as a Los Angeles-based correspondent.