Buddhists carry a dragon-shaped lantern during a lotus lantern parade in celebration of the upcoming birthday of Buddha in Seoul, South Korea, May 7, 2016. (Photo by Kim Hong-Ji/Reuters)

Russian Tu-95MS strategic bombers fly in formation during rehearsals for the Victory Day military parade, with St. Basil's Cathedral seen in the foreground, in central Moscow May 5, 2015. Russia will celebrate the 70th anniversary of the victory over Nazi Germany in World War Two on May 9. (Photo by Tatyana Makeyeva/Reuters)

Horsemen take part in the Durbar festival parade in Zaria, Nigeria September 14, 2016. It is celebrated at the culmination of Muslim festivals Eid al-Fitr and Eid al-Adha. It begins with prayers, followed by a parade of the Emir and his entourage on horses, accompanied by music players, and ending at the Emir's palace. (Photo by Afolabi Sotunde/Reuters)

In this aerial view the officers' building and an auditorium stand at the former Soviet military base on January 26, 2017 in Wuensdorf, Germany. Wuensdorf, once called “The Forbidden City”, was the biggest base for the Soviet armed forces in communist East Germany from 1945 until the last Soviet troops left in the early 1990s following the end of the Cold War and the reunification of Germany. (Photo by Sean Gallup/Getty Images)

An Afghan National Army (ANA) soldier assigned to the Mobile Strike Force Kandak fires a RPG-7 rocket-propelled grenade launcher during a live-fire exercise supervised by the Marines with the Mobile Strike Force Advisor Team on Camp Shorabak, Helmand province, Afghanistan, May 20, 2013. The Marines with the Mobile Strike Force Advisor Team instructed and mentored their ANA counterparts on how to properly utilize their weapons systems. (Photo by SSgt Ezekiel R. Kitandwe/RCT 7)

Army paratroopers carry the casket of Private Howard at the Wellington Cathedral on December 21, 2010 in Wellington, New Zealand. Private Howard was serving with the British army when was killed by friendly fire from a US Air Force plane in Helmand Province, Afghanistan earlier this month. Private Howard is the fifth NZ-born soldier to be killed in action in Afghanistan. (Photo by Marty Melville/Getty Images)

Afghan National Army (ANA) soldiers sit waiting to return their weapons after a day of traning at the Kabul Military Training Center (KMTC) October 3, 2010 in Kabul, Afghanistan. There are between 5,000 to 7,000 troops on the training facility in eight-week cycles trained by the coalition forces to ultimately take over the role of military operations in the country. (Photo by Paula Bronstein/Getty Images)