Afghan security forces patrol near their base in the Marjah district of Helmand province on Dec. 23. Dozens of Marines were killed in Marjah five years ago, and since then the Taliban have slipped back in. Now American forces are increasingly being drawn back into the fight. Noor Mohammad/AFP/Getty Images hide caption

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Three migrants from Afghanistan walk along the A3 highway shortly after they crossed into Germany on August 30, 2015, near Neuhaus am Inn, Germany. Police detained them shortly after and took them to a registration center for asylum seekers. Germany has welcomed many refugees — but now is discouraging Afghans who are seeking better economic prospects. Sean Gallup/Getty Images hide caption

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Army Sgt. Bowe Bergdahl leaves a military courthouse Tuesday in Fort Bragg, N.C. Bergdahl was arraigned on charges of desertion and endangering troops stemming from his decision to leave his outpost in Afghanistan in 2009. Sara D. Davis/Getty Images hide caption

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NPR's Steve Inskeep interviews President Obama at the White House. Kainaz Amaria/NPR hide caption

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Two young Afghan women, Shopirai Otmonkhel and Zahra Karimi Nooristani, hold the Afghan flag on an unnamed peak in Panjshir. They were among 13 Afghan girls and young women who took part in a 16-day climbing expedition in northeast Afghanistan. Courtesy of Emilie Drinkwater/Ascend hide caption

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Senior Airman Frances Gavalis tosses unserviceable uniform items into a burn pit at Balad Air Base, Iraq in 2008. The military destroyed uniforms, equipment and other materials in huge burn pits in Iraq and Afghanistan. Some veterans say those pits are responsible for respiratory problems they are now experiencing. Senior Airman Julianne Showalter/USAF hide caption

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