Tajammu Al-Ezza brigade fighters react while firing a Grad shell towards forces of Syria's President Bashar Al-Assad stationed in Salhab village, Hama countryside, May 7, 2015. (Photo by Mohamad Bayoush/Reuters)

A man holds a cow at the cattle market in Maiduguri, Nigeria, March 9, 2016. A Nigerian government push to strangle the Boko Haram insurgency has shut down the cattle trade that sustained the city of Maiduguri, leaving many residents with no livelihood, including many of the two million people displaced by the war. In recent months the army has taken back much of the territory lost to the jihadists during the five-year insurgency. (Photo by Afolabi Sotunde/Reuters)

Canadian soldiers from the Royal 22nd Regiment take up a position during a non-combative extraction operation in a simulated village as part of Rim of the Pacific (RIMPAC) 2016 exercise held at Camp Pendleton, California United States, July 11, 2016. (Photo by Mike Blake/Reuters)

In this Wednesday, January 7, 2015 photo, a Sri Lankan Catholic devotee Rita Anthony kisses her rosary as she prays inside her house in Colombo, Sri Lanka. The Vatican has said that it hopes that Sri Lanka's Christians can play a role in helping heal the wounds of the island nation's bloody 25-year civil war, when the Tamil Tiger rebels fought to create a separate homeland in the north for the minority Tamils, who are mostly Hindu. The war came to a bloody end in 2009, but many Tamils say they feel forgotten by the central government, which is dominated by the country's ethnic Sinhala majority, which is overwhelmingly Buddhist. Sri Lanka's Christians come from both the Tamil and the Sinhala communities, making them a natural bridge between the two sides. (Photo by Eranga Jayawardena/AP Photo)

“Shortly after he arrived, Van Agtmael witnessed the aftermath of this suicide bombing at a cafe that soldiers frequented in Mosul. Nine people died and 23 were wounded”. (Photo and caption by Van Agtmael/Harrison Jacobs/Magnum Photos)

“Life in War” (FotoEvidence Press) by Iranian photographer Majid Saeedi is probably the only book about Afghanistan that doesn’t show images of war. For ten years his camera photographed daily life in the context of war. His photographs reveal the humanity of a people living through decades of war. Here: Afghan men escape increasing summer temperatures by wading in the Qarga reservoir on July 9, 2010 in a suburb of Kabul, Afghanistan. (Photo by Majid Saeedi/Getty Images)

These Arab recruits line up in a barracks square in the British Mandate of Palestine, on December 28, 1940, for their first drill under a British solider. Some 6,000 Palestinian Arabs signed up with the British Army during the course of World War II. (AP Photo)