A man and a woman both wounded by what locals say was recent shelling by Ukrainian forces, react as they sit in an ambulance in Donetsk August 23, 2014. (Photo by Maxim Shemetov/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)

North Korean leader Kim Jong Un is hugged by children during his visit to Samjiyon County in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang November 28, 2016. (Photo by Reuters/KCNA)

A contestant performs in wooden Pujllay dance shoes known as “ojotas”, in a contest to elect the Queen of Great Power, in La Paz, Bolivia, Friday, May 24, 2019. The largest religious festival in the Andes choses its queen in a tight contest to head the Festival of the Lord Jesus of the Great Power, mobilizing thousands of dancers and more than 4,000 musicians into the streets of La Paz. (Photo by Juan Karita/AP Photo)

Five-year-old Ghazal al-Hussein poses inside a classroom in the rebel-controlled area of Maarshureen village in Idlib province, Syria March 12, 2016. March 15 marks the 5th anniversary of peaceful protests against Syria's President Bashar al-Assad, leading to the devastating civil conflict in the country. These are portraits of five-year-old Syrian children who have only known conflict in their country. (Photo by Khalil Ashawi/Reuters)

A pistol is lies near the body of a drug suspect who was killed with two others in an alleged “buy-bust” operation before dawn on Friday, September 30, 2016, in Caloocan city, north of Manila, Philippines, in the continuing “War on Drugs” campaign of President Rodrigo Duterte. Duterte said he would be “happy to slaughter” 3 million addicts. (Photo by Bullit Marquez/AP Photo)

The BADGER shot was a 23 kiloton nuclear bomb. Over 2,000 US soldiers were within 3.7 kilometers of the explosion. (Photo by Alamy Stock Photo)

Egyptian bootblacks cleaning a European's shoes in Cairo. (Photo by Hulton Archive/Getty Images). Circa 1870