Hospital Corpsman Shannon Crowley, with a Marine Corps. Female Engagement Team, in Musa Qala, Afghanistan, in November 2010. Paula Bronstein/Getty Images hide caption

itoggle caption Paula Bronstein/Getty Images

Prince Harry, known when on duty as "Capt. Wales," in the cockpit of an Apache helicopter while he was in Afghanistan last month. John Stillwell/PA wire/pool/EPA /Landov hide caption

itoggle caption John Stillwell/PA wire/pool/EPA /Landov

Children often show signs of trauma from their experiences inside Syria. A U.N. team interviewing Syrian children in a refugee camp found that most lost a loved one in the fighting, and almost half have post-traumatic stress disorder. Jodi Hilton for NPR hide caption

itoggle caption Jodi Hilton for NPR

An almost deserted, rubble-filled street in Aleppo, Syria (Oct. 9, 2012). Tauseef Mustafa /AFP/Getty Images hide caption

itoggle caption Tauseef Mustafa /AFP/Getty Images

Palestinians react after they checked the body of their family member killed in an Israeli air strike, at Al-Adwan Hospital in Gaza City on Tuesday. Chen Xu/Xinhua /Landov hide caption

itoggle caption Chen Xu/Xinhua /Landov

Fleeing the fighting: Internally displaced Congolese sit inside a United Nations base in Monigi, near Goma, as they seek shelter from the violence. Phil Moore/AFP/Getty Images hide caption

itoggle caption Phil Moore/AFP/Getty Images

An Israeli soldier lies on the ground as missiles are fired from an Iron Dome anti-missile station on Thursday near the city of Beer Sheva, Israel. The Iron Dome was activated to intercept incoming rockets launched from Gaza. Ilia Yefimovich/Getty Images hide caption

itoggle caption Ilia Yefimovich/Getty Images