A drilling rig near Kennedy, Texas, on May 9. U.S. oil output is surging so fast that the United States could soon overtake Saudi Arabia as the world's biggest producer. Eric Gay/AP hide caption

itoggle caption Eric Gay/AP

President Obama and Mitt Romney are both calling on the U.S. to become less dependent on foreign oil, though their plans differ. Here, workers with Bramwell Petroleum set up a derrick for a new oil well near Spivey, Kan., in March. Mike Hutmacher/MCT/Landov hide caption

itoggle caption Mike Hutmacher/MCT/Landov

Soldiers use DCGS-A software at Aberdeen Proving Ground in Maryland. U.S. Army hide caption

itoggle caption U.S. Army

Iranian President Mahmoud Ahmadinejad (center) visits the Natanz Uranium Enrichment Facility in April 2008. Israel and the U.S. targeted the facility in 2009 with the Stuxnet cyberattack. AP hide caption

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Republican presidential candidate Mitt Romney meets with members of the Veterans of Foreign Wars after his speech at the VFW National Convention in Reno, Nev., on July 24. Rich Pedroncelli/AP hide caption

itoggle caption Rich Pedroncelli/AP

Iranian workers make repairs to a unit at Tehran's oil refinery in November 2007. It's estimated that a Western oil embargo is costing Iran about $4.5 billion each month in lost revenue. Vahid Salemi/AP hide caption

itoggle caption Vahid Salemi/AP

German Chancellor Angela Merkel talks with European Central Bank President Mario Draghi (left) and Italian Prime Minister Mario Monti (right) during a summit of European leaders in Brussels. They reached an agreement on a growth plan for the continent, and world markets surged. Bertrand Langlois /AFP/Getty Images hide caption

itoggle caption Bertrand Langlois /AFP/Getty Images

James Clapper, director of national intelligence, leaves a closed-door joint meeting with the Senate and House Intelligence committees on June 7. Clapper ordered an inquiry into security leaks to be concluded next week. Mark Wilson/Getty Images hide caption

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The CIA took considerable heat over Iraq, where weapons of mass destruction weren't found. Now, as the agency assesses Iran, it invites an NPR correspondent to its headquarters for a rare chat about the issue. Andrew Harrer/Bllomberg via Getty Images hide caption

itoggle caption Andrew Harrer/Bllomberg via Getty Images

If sanctions continue, Iran's tankers could fill up with surplus oil and leave the country with no place to store its continued production. Kamran Jebreili/AP hide caption

itoggle caption Kamran Jebreili/AP