A French military drone takes off in December 2010 from a U.S. airbase in Bagram, Afghanistan. Joel Saget/AFP/Getty Images hide caption

itoggle caption Joel Saget/AFP/Getty Images

A Malian troop member checks bushes after a military raid in the Wagoudou forest. Serge Daniel/AFP/Getty Images hide caption

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David Easterling, manager of the Suicide Prevention Program at Fort Riley in Kansas spray-paints Army boots white in 2009 as part of an on-base display to commemorate the six Fort Riley soldiers who committed suicide in 2008. Chris Hondros/Getty Images hide caption

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These gas masks were reconditioned at the Edgewood Arsenal for civilian defense use during World War II. Later, in the 1950s and '60s, the arsenal near the Chesapeake Bay was used for secret chemical weapons testing run by the U.S. Army. Jack Delano/Library of Congress hide caption

itoggle caption Jack Delano/Library of Congress

Maralynn Bernstein (bottom left), the veterans services coordinator for the University of Arizona, confers with Cody Nicholls, director of the Veterans Education and Transition Services Center, at the school's Veterans Center in Tucson. Larry Abramson/NPR hide caption

itoggle caption Larry Abramson/NPR