A decade ago, U.S. soldiers were fighting and rebuilding in the Iraqi cities of Mosul and Tikrit. The past few weeks have seen those cities, among others, fall to the Sunni militant group ISIS. Here, a member of the Kurdish Peshmerga forces stands guard Thursday near an ISIS checkpoint in Mosul. Karim Sahib/AFP/Getty Images hide caption

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Arlington National Cemetery is the final resting place for more than 400,000 men and women. Most were members of the armed forces who served in active duty — but not all. Paul J. Richards/AFP/Getty Images hide caption

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D-Day veteran Ralph Frias was a linguist and forward observer with the 19th Corps 963 Battalion and went over the Normandy cliffs in search of American paratroopers. After the fighting, he interviewed German POWs and French civilians. Amy Ta/NPR hide caption

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Soldiers returning from the Pacific wave from the deck of the USS General Mitchell on Dec. 11, 1945. Much of the health care demand in the VA system is from veterans of earlier wars. AP hide caption

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