Brig. Gen. Viet Luong of the 1st Cavalry Division came to the United States in the 1970s after his family fled Vietnam in the waning days of the war there. He's now leading the effort to train Afghan soldiers to fight the Taliban. David Gilkey/NPR hide caption

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An artillery gun fires a round at Taliban fighters in the hills of Nangahar Province. David Gilkey/NPR hide caption

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Afghan commandos move through a smokescreen during a training exercise at Camp Commando on the outskirts of Kabul, Afghanistan. David Gilkey/NPR hide caption

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Sgt. Courtney White carries her machine gun before a live fire exercise at the Marine base at Twentynine Palms, Calif. David Gilkey/NPR hide caption

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Lance Cpl. Brittany Dunklee talks with her fellow Marines. David Gilkey/NPR hide caption

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Female and male Marines prepare for a live-fire exercise at Twentynine Palms, a training camp in the Mojave Desert. David Gilkey/NPR hide caption

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