The aircraft carrier USS Enterprise, shown departing from Naval Station Norfolk on Jan. 13, is now in the Red Sea, with its dozens of warplanes, waiting to see if it's needed for any Libyan operation. U.S. Navy/Getty Images hide caption

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President Ronald Reagan gestures during a news conference at the White House in January 1986, when he said there was "irrefutable evidence" that Libyan leader Moammar Gadhafi was involved in airport attacks in Rome and Vienna in December 1985. Scott Stewart/AP hide caption

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An F-15C Eagle aircraft returns to base after a mission during Operation Deny Flight, the United Nations-sanctioned no-fly-zone action over Bosnia and Herzegovina in 1998. Retired Navy Capt. Tom Parker, who flew no-fly-zone missions in the Balkans, says the strategy could work in Libya. But Defense Secretary Robert Gates and others argue that it wouldn't be easy. U.S. Air Force/Getty Images hide caption

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A U.S. soldier records video footage while blowing up an improvised explosive device found by an Afghan villager in Kandahar province on Dec. 29. The military is using new technology — sensors attached to American aircraft — to sniff out roadside bombs. Behrouz Mehri/AFP/Getty Images hide caption

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Frank Buckles during a 2008 ceremony honoring him on Capitol Hill in Washington, D.C. Karen Bleier/AFP/Getty Images hide caption

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A cargo ship transits the Suez Canal en route from the Mediterranean Sea to the Gulf of Suez at the city of Suez, Egypt, on Feb. 2. Egypt controls the canal, which is vital to U.S. interests. Emilio Morenatti/AP hide caption

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The USS Enterprise passes behind a mosque as it makes its way through the Suez Canal in the city of Suez, Egypt, on Aug. 1, 2007. Ben Curtis/AP hide caption

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Anti-government protesters offer their evening prayers in front of an Egyptian army tank securing the area during a protest Monday in Cairo's Tahrir Square. A coalition of opposition groups called for a million people to take to Cairo's streets Tuesday to demand the removal of Egyptian President Hosni Mubarak. Lefteris Pitarakis/AP hide caption

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U.S. Marines attend a role call on the flight deck of the USS Essex, a multipurpose amphibious assault ship, in November. Defense Secretary Robert Gates says he wants to reduce the Marine Corps by 15,000 to 20,000 in the coming years. Ed Jones/Getty Images hide caption

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U.S. Marine Corps Gen. James Amos testifies on Capitol Hill in September. Amos, now the Marine Corps' top officer, told Congress earlier this month that "don't ask, don't tell" should remain the law of the land. Alex Brandon/AP hide caption

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