A migrant smokes a cigarette as he waits among others to cross the Croatian border near the village of Berkasovo, Serbia October 19, 2015. Thousands of migrants clamoured to enter European Union member Croatia from Serbia on Monday after a night spent in the cold and mud of no-man's land, their passage west slowed by a Slovenian effort to impose limits on the flow to western Europe. (Photo by Marko Djurica/Reuters)

Models of Cold War-era Allied (L) and Soviet Bloc weaponry face one another at the new Bundeswehr Military History Museum (Militaerhistorisches Museum der Bundeswehr, or MHM) on October 11, 2011 in Dresden, Germany. The museum, redesigned by star architect Daniel Libeskind, traces Germany military history from 1300 to the present, including during the Nazi period and the Cold War, and also examines the influence of the military on popular culture. (Photo by Sean Gallup/Getty Images)

Britain's Prince Harry meets Chewbacca during a visit to the Star Wars film set at Pinewood Studios near Iver Heath, west of London, Britain, April 19, 2016. Prince William and Prince Harry are touring Pinewood to visit the production workshops and meet the creative teams working behind the scenes on the Star Wars films. (Photo by Adrian Dennis/Reuters)

A young evacuee of Japanese ancestry waits with the family baggage before leaving by bus for an assembly center in California, in this April 1942 handout photo. February 19, 2017 marks the 75th anniversary of FDR signing executive order 9066, authorizing the internment of Japanese Americans during World War Two. (Photo by Courtesy Clem Albers/Department of the Interior/War Relocation Authority/National Archives/Reuters)

Crowds look on as Xolo the Giant Dog, one of the giant Royal De Luxe street puppets taking part in Liverpool's World War I centenary commemorations, walks through the streets of Liverpool on July 25, 2014 in Liverpool, England. French street theatre company Royal de Luxe are putting on a show throughout the city as part of Liverpool's World War I centenary commemorations from July 23-27. The giant puppet grandmother has slept in the hall for two days as part of “Memories of August 1914”. As the giants tour the city the Little Girl Giant and her dog Xolo will meet up with the giant Grandmother telling the story of life leading up to World War One. (Photo by Christopher Furlong/Getty Images)

June 21: “World War Z”. Brad Pitt battles zombie apocalypse in $170 million film by “Quantum of Solace” director Marc Forster. This publicity photo released by Paramount Pictures shows, center, Brad Pitt as Gerald Lane in a scene from the film, “World War Z”, from Paramount Pictures and Skydance Productions in association with Hemisphere Media Capital and GK Films. (Photo by Jaap Buitendijk/AP Photo/Paramount Pictures)

Members of the Albert Battery perform a gun salute during the Anzac Day dawn service held by the Currumbin RSL on the Gold Coast in Currumbin, Australia, 25 April 2016. The Anzac day marks the landing of the Australian and New Zealand Army Corps (Anzac) troops at Gallipoli in what is today Turkey during WWI. World War One, also called the Great War, according to official statistics cost more than 37 million military and civilian casualties between 1914 and 1918. (Photo by Glenn Hunt/EPA)

A serviceman kisses the main icon for the Russian Armed Forces' main cathedral, delivered at the Church of Our Lady the Healer in Rostov-On-Don, Russia on May 15, 2018. The Russian Armed Forces' main cathedral is to be built in Patriot Military Park in Kubinka outside Moscow by 2020, the year of the 75th anniversary of the victory of the Soviet Red Army over Nazi Germany in the 1941-45 Great Patriotic War, the Eastern Front of World War II. (Photo by Valery Matytsin/TASS)