Afghan security forces and British soldiers inspect the site of a suicide attack in the heart of Kabul, Afghanistan, on Saturday. Three American civilian contractors are reportedly among the dead. Massoud Hossaini/AP hide caption

itoggle caption Massoud Hossaini/AP

Afghan security forces inspect a suicide bombing attack on Aug. 10 near the main gate of Kabul's international airport. It was one of a series of recent attacks in the Afghan capital that have left at least 50 dead. Violence in Afghanistan has increased since U.S. combat troops pulled out last year. Massoud Hossaini/AP hide caption

itoggle caption Massoud Hossaini/AP

A 1998 file photo of Ayman al-Zawahri speaking at a news conference in Khost, Afghanistan. The reclusive al-Qaida leader says he has pledged support to the new chief of the Taliban, Mullah Akhtar Mansoor. Mazhar Ali Khan/AP hide caption

itoggle caption Mazhar Ali Khan/AP

National Geographic photographer Steve McCurry, shown in Kuwait in 1991, says his big break came at a refugee camp near Peshawar, Pakistan, after he heard the sound of children laughing. Courtesy of Steve McCurry hide caption

itoggle caption Courtesy of Steve McCurry

John Sopko, special inspector general for Afghanistan reconstruction, testifies on Capitol Hill last June. In a letter released Thursday, Sopko says the U.S. may have been paying for "ghost schools, ghost students and ghost teachers" in Afghanistan. Charles Dharapak/AP hide caption

itoggle caption Charles Dharapak/AP

A group of Afghan women are attempting to reach the 24,580-foot summit this summer. In mid-May, two of the climbers, along with two American chaperones, visited Afghanistan's highest mountain to see the terrain firsthand in preparation for the historic climb. Soraya Sarhaddi-Nelson/NPR hide caption

itoggle caption Soraya Sarhaddi-Nelson/NPR

Lt. Gen. Abdul Raziq is the police chief widely credited with bringing much greater security to the southern Afghan city of Kandahar. But critics accuse him of human rights abuses including torture and extrajudicial killings. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

John Sopko, Special Inspector General for Afghanistan Reconstruction, testifies on Capitol Hill last June. Sopko says the Afghans are still having trouble managing the money the U.S. sends to the country. The U.S. has spent $110 billion on Afghanistan's reconstruction since 2002. Charles Dharapak/ASSOCIATED PRESS hide caption

itoggle caption Charles Dharapak/ASSOCIATED PRESS

Brig. Gen. Akram Samme coordinates his men at Camp Eagle in the Shah Joy district of Zabul province in southern Afghanistan. He is a commander in the major operation against the Taliban that's currently under way. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

The remains of an inflatable boat that passed illegally from the coast of Turkey rest in October 2014 on the shore 10 miles from Mytilene, Greece. Thirty-four immigrants from Syria, among them one woman and three children, made a dangerous night journey Sept. 26. Orestis Panagiotou/EPA/LANDOV hide caption

itoggle caption Orestis Panagiotou/EPA/LANDOV

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

itoggle caption David Gilkey/NPR

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

itoggle caption David Gilkey/NPR

First Lt. Ashley White was one of some 55 to 60 women selected for cultural support teams that deployed to Afghanistan in 2011. She did not make it home. She was the first woman to die and be honored alongside the Army Rangers with whom she served. Courtesy of the White Family hide caption

itoggle caption Courtesy of the White Family

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

itoggle caption David Gilkey/NPR