US Navy crew man machine-guns as they stand aboard a Riverine Command Boat off the coast of Bahrain's Salman port, near Manama, on May 12, 2013, one day before the start of the biggest exercise of mine countermeasure maneuvers in the Arabian Gulf. The US Navy along with other 40 nations are conducting the games. AFP PHOTO/MARWAN NAAMANI (Photo credit should read MARWAN NAAMANI/AFP/Getty Images)
Smoke billows from buildings after reported air strikes by the Saudi-led coalition on arms warehouses at Al-Dailami air base, on September 29, 2015, north of the capital Sanaa. AFP PHOTO / MOHAMMED HUWAIS (Photo credit should read MOHAMMED HUWAIS/AFP/Getty Images)
Military delegates attend the closing ceremony on the final day of the Vietnam Communist Party's 12th National Congress in Hanoi on January 28, 2016. Vietnam's top communist leader Nguyen Phu Trong was re-elected on January 27 in a victory for the party's old guard which some fear could slow crucial economic reforms in the fast-growing country. AFP PHOTO / POOL / Kham / AFP / POOL / KHAM. (Photo credit should read KHAM./AFP/Getty Images)
U.S. Soldiers with 1st Battalion, 64th Armor Regiment, 1st Armored Brigade Combat Team, 3rd Infantry Division, look down range in a M1A2 Sepv2 Abrams Main Battle Tank as AH-64 Apaches hover above during a combined arms live-fire exercise at the Joint Multinational Training Command in Grafenwoehr, Germany, Nov. 19, 2015. The exercise was the culminating event for Combined Resolve V, a U.S. Army Europe-directed multinational exercise with more than 4,600 participants from 13 NATO and European partner nations. Combined Resolve V is designed to exercise the U.S. Army’s regionally aligned force to the U.S. European Command area of responsibility with multinational training at all echelons. This exercise will train participants to function together in a joint, multinational and integrated environment and train U.S. rotational forces to be more flexible, agile and to better operate alongside our NATO allies.
(U.S. Army photo by Visual Information Specialist Markus Rauchenberger/released)
Iraqi protesters gather in the parade grounds outside the parliament in Baghdad's heavily fortified "Green Zone" on May 1, 2016, a day after supporters of Shiite cleric Moqtada al-Sadr broke into the area after lawmakers again failed to approve new ministers.
Protesters were withdrawing from Baghdad's Green Zone after breaking into the fortified area and storming Iraq's parliament in an unprecedented security breach the day before. The move, which lessens the pressure on politicians in Baghdad, came as rare bombings in the south killed 33 people and wounded dozens. / AFP / HAIDAR MOHAMMED ALI (Photo credit should read HAIDAR MOHAMMED ALI/AFP/Getty Images)
An Iraqi Kurdish Peshmerga fighter fires at Islamic-State (IS) militant positions, from his position on the top of Mount Zardak, a strategic point taken 3 days ago, about 25 kilometres east of Mosul on September 9,2014. Kurdish forces in the north have been bolstered by US strikes and took control of Mount Zardak, a strategic site that provides a commanding view of the surrounding area, a senior US officer said. AFP PHOTO/ JM LOPEZ (Photo credit should read JM LOPEZ/AFP/Getty Images)
BEIJING - OCTOBER 01: Chinese People's Liberation Army (PLA) sailors march pass Tiananmen Square during the celebration of the 60th anniversary of the founding of the People's Republic of China on October 1, 2009 in Beijing, China. The grand celebrations to commemorate the 60th anniversary of the founding of the People's Republic of China included a military parade and mass pageant consisting of about 200,000 citizens in Tiananmen Square. (Photo by Feng Li/Getty Images)
CAMP LEJEUNE, NC - JUNE 16: A pile of gas masks, still dirty from use in Iraq, lies in a refurbishing facility June 16, 2003 in Camp Lejeune, North Carolina. Camp Lejeune, home base to many of the Marines who saw fierce combat in Iraq, is entering its post-Iraq phase by restocking its base and slowly welcoming troops home. (Photo by Chris Hondros/Getty Images)
US Supreme Commander of the North Atlantic Treaty Organization (NATO) General Dwight David Eisenhower (1890-1969) presents his first yearly report to the press at NATO's headquarters in Rocquencourt on April 2, 1952. AFP PHOTO (Photo credit should read /AFP/GettyImages)
An image of a US P8 Poseidon plane can be seen on a monitor in the cockpit of a Royal New Zealand Air Force P3 Orion while flying to the search zone to help find missing Malaysia Airlines flight MH370, over the Indian Ocean on March 31, 2014. No time limit will be imposed on the search for MH370 because the world deserves to know what happened, Australian Prime MinisterTony Abbott said, as a ship equipped to locate the plane's "black box" prepared to set sail. AFP PHOTO / POOL / Rob GRIFFITH (Photo credit should read ROB GRIFFITH/AFP/Getty Images)
This picture taken from a Vietnam Coast Guard ship on May 14, 2014 shows a Vietnamese Coast Guard ship (L) is challended by a China Coast Guard ship near to the site of a Chinese drilling oil rig (R, background) being installed at the disputed water in the South China Sea off Vietnam's central coast. Vietnam National Assembly's deputies gathered for their summer session are discussing the escalating tension with China over the South China Sea's contested water. AFP PHOTO/HOANG DINH Nam (Photo credit should read HOANG DINH NAM/AFP/Getty Images)
INDIAN SPRINGS, NV - NOVEMBER 17: (EDITORS NOTE: Image has been reviewed by the U.S. Military prior to transmission.) An MQ-9 Reaper remotely piloted aircraft (RPA) flies by during a training mission at Creech Air Force Base on November 17, 2015 in Indian Springs, Nevada. The Pentagon has plans to expand combat air patrols flights by remotely piloted aircraft by as much as 50 percent over the next few years to meet an increased need for surveillance, reconnaissance and lethal airstrikes in more areas around the world. (Photo by Isaac Brekken/Getty Images)