Power Play: U.S. oil production provides foreign policy flexibility

While the country is still far from free of its dependence on foreign oil, the efforts of the North American producers already are making a difference.

The country's oil imports peaked in 2005 at more than 10.1 million barrels per day. A nearly 50-year trend of steadily increasing imports was then suddenly and dramatically reversed as improved drilling techniques have allowed domestic producers to increase their oil output while the recession and conservation efforts have driven down demand.

As a result, the country's oil imports declined to 8.9 million barrels per day last year, down by more than 1.1 million barrels per day from the 2005 peak.

Production also has steadily increased over the past five years in Canada, Brazil, Saudi Arabia and other countries.

The combined global output increase has allowed the United States and European Union to enforce strict sanctions on Iran — the world's No. 5 oil producer — because of its nuclear efforts.

Beginning June 28, a new set of U.S. sanctions bars foreign banks that buy oil from Iran from doing business with the U.S. banking system.

European Union restrictions that began July 1 make it illegal for EU countries to import Iranian oil and refined products. The EU represented about 20 percent of Iran's exports last year. The EU plan also prevents European insurance companies from providing coverage for tankers carrying Iranian oil.