US soldiers and an Afghan police officer take a break whilst on patrol near Kandahar Airfield on June 3, 2014. Members of the 1st Battalion, 12th Regiment, 4th Brigade Combat Team, 4th Infantry Division patrolled areas near Kandahar Airfield to protect the base from rocket attacks, and also visited Afghan police and polling stations to check on the security for the upcoming presidential election runoff. AFP PHOTO/Brendan SMIALOWSKI (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images)
TAJI, IRAQ - APRIL 12: A U.S. Army trainer (L), instructs Iraqi Army recruits at a military base on April 12, 2015 in Taji, Iraq. U.S. forces, currently operating in 5 large bases throught Iraq, are training thousands of Iraqi Army combat troops, trying to rebuild a force they had origninally trained before the U.S. withdrawal from Iraq in 2010. Members of the U.S. Army's 5-73 CAV, 3BCT, 82nd Airborne Division are teaching members of the newly-formed 15th Division of the Iraqi Army, as the Iraqi government launches offensives to try to recover territory lost to ISIS last year. (Photo by John Moore/Getty Images)
In this night exposure photograph US soldiers from Bravo and Delta Company, 2-87 Infantry Battalion, 3rd Brigade Combat Team and Afghan national security forces board a Chinook military helicopter at the Forward Operating Base Pasab in Zahri district, Kandahar province southern Afghanistan late August 14, 2011 during a ground and air assault operation in Maiwand district against Taliban insurgents. According to Major Kirby Dennis, operations officer of Task Force 2-87 the five hour US army operation resulted in the capature of eight individuals, including two suspected Taliban leaders and assorted bomb making components. AFP PHOTO / ROMEO GACAD (Photo credit should read ROMEO GACAD/AFP/Getty Images)
Iraqi Shiite fighters from the Popular Mobilisation units, fighting Islamic State (IS) jihadists alongside Iraqi government forces, are seen opposite Baiji's main refinery north of the multi-ethnic Iraqi city of Tikrit on October 15, 2015. Iraqi forces defused booby traps and hunted down holdout jihadists in the strategic Baiji area as part of their biggest advance against the Islamic State group in months. After retaking most of the refinery to the north of the city, at a crossroads between several frontlines, security forces were sweeping the sprawling complex for bombs and die-hard jihadists. AFP PHOTO / MOHAMMED SAWAF (Photo credit should read MOHAMMED SAWAF/AFP/Getty Images)
