National oil production, which declined steadily to 4.95 million barrels a day in 2008 from 9.6 million in 1970, has risen over the last four years to nearly 5.7 million barrels a day. The Energy Department projects that daily output could reach nearly seven million barrels by 2020. Some experts think it could eventually hit 10 million barrels — which would put the United States in the same league as Saudi Arabia.

This surge is hardly without consequences. Some areas of intense drilling activity, including northeastern Utah and central Wyoming, have experienced air quality problems. The drilling technique called hydraulic fracturing, or fracking, which uses highly pressurized water, sand and chemical lubricants that help force more oil and gas from rock formations, has also been blamed for wastewater problems. Wildlife experts also warn that expanded drilling is threatening habitats of rare or endangered species.

Greater energy independence is “a prize that has long been eyed by oil insiders and policy strategists that can bring many economic and national security benefits,” said Jay Hakes, a senior official at the Energy Department during the Clinton administration. “But we will have to work through the environmental issues, which are a definite challenge.”

The increased production of fossil fuels is a far cry from the energy plans President Obama articulated as a candidate in 2008. Then, he promoted policies to help combat global warming, including vast investments in renewable energy and a cap-and-trade system for carbon emissions that would have discouraged the use of fossil fuels.

More recently, with gasoline prices rising and another election looming, Mr. Obama has struck a different chord. He has opened new federal lands and waters to drilling, trumpeted increases in oil and gas production and de-emphasized the challenges of climate change. On Thursday, he said he supported expedited construction of the southern portion of the proposed Keystone XL oil pipeline from Canada.

Mr. Obama’s current policy has alarmed many environmental advocates who say he has failed to adequately address the environmental threats of expanded drilling and the use of fossil fuels. He also has not silenced critics, including Republicans and oil executives, who accuse him of preventing drilling on millions of acres off the Atlantic and Pacific Coasts and on federal land, unduly delaying the decision on the full Keystone project and diverting scarce federal resources to pie-in-the-sky alternative energy programs.

Just as the production increase was largely driven by rising oil prices, the trend could reverse if the global economy were to slow. Even so, much of the industry is thrilled at the prospects.