A military enthusiast dressed as World War Two Red Army officer sits in a cafe as he marks the 75th anniversary of the Nazi Germany invasion, in Brest, Belarus June 21, 2016. (Photo by Vasily Fedosenko/Reuters)

Members of the Iraqi Army fire towards Islamic State militant positions at the south of Mosul, Iraq December 10, 2016. (Photo by Alaa Al-Marjani/Reuters)

An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

Then U.S. Army First Lieutenant Kirsten Griest (C) and fellow soldiers participate in combatives training during the Ranger Course on Fort Benning, Georgia, in this handout photograph taken on April 20, 2015 and obtained on August 20, 2015. When Griest and another woman completed the daunting U.S. Army Ranger school this week they helped end questions about whether women can serve as combat leaders, as the Pentagon is poised to open new roles, including elite Navy SEALs, to women in coming months. The feat by Griest and First Lieutenant Shaye Haver followed a re-evaluation of the role of women after their frontline involvement in Iraq and Afghanistan and the end of a rule barring them from combat roles in 2013. (Photo by Spc. Nikayla Shodeen/Reuters/U.S. Army)

Members of the New People's Army (NPA) female guerrillas perform a cultural show during the release of a Philippines army soldier in Sugbongcogon town, Misamis Oriental, southern Philippines, November 20, 2015. NPA spokesperson Allan Juanito warned that they will seize more soldiers to exchange them with the government as "Prisoners of war". (Photo by Froilan Gallardo/Reuters)

A Nepalese army solder stand next to a horse during the “Ghodejatra” Horse Race festival, which is organised by the Nepal Army, in Kathmandu, Nepal, April 7, 2016. Ghode Jatra, the horse racing festival of Nepal, celebrated on the New Moon day of mid March or early April is among the important celebrations of the Kathmandu Valley. Grand horse parade including various acrobatic style of shows are performed by Nepal military at Tundikhel-a fenced parade ground located in the heart of Kathmandu city. (Photo by Navesh Chitrakar/Reuters)

Soviet Army soldiers sit on their tanks in front of the Czechoslovak Radio station building in central Prague during the first day of Soviet-led invasion to then Czechoslovakia on August 21, 1968. (Photo by Libor Hajsky/Reuters)

Ethnic Wa performer dressed as United Wa State Army (UWSA) soldiers perform a traditional dance in Mongmao, Wa territory in northeast Myanmar October 1, 2016. (Photo by Soe Zeya Tun/Reuters)