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)

A civilian trains to throw Molotov cocktails to defend the city, as Russia's invasion of Ukraine continues, in Zhytomyr, Ukraine March 1, 2022. (Photo by Viacheslav Ratynskyi/Reuters)

A child looks out from a bus window after fleeing from Ukraine to Romania, following Russia's invasion of Ukraine, at the border crossing in Siret, Romania, March 13, 2022. (Photo by Clodagh Kilcoyne/Reuters)

A mural is seen on a heavily damaged residential building in the frontline town of Avdiivka, Donetsk region on April 25, 2023, amid the Russian invasion of Ukraine. (Photo by Anatolii Stepanov/AFP Photo)

A woman dressed as an angel takes a break from greeting children at a public library in Irpin, northwest of Kyiv, on December 23, 2022, amid the Russian invasion of Ukraine. (Photo by Genya Savilov/AFP Photo)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

People take part in a military exercise for civilians conducted by veterans of the Ukrainian National Guard Azov battalion, amid threat of Russian invasion, in Kyiv, Ukraine on January 30, 2022. (Photo by Gleb Garanich/Reuters)

A Ukrainian gunner sits in his 2S1 Gvozdika (122-mm self-propelled howitzer) on the front line in Southern Ukraine on October 8, 2022, amid the Russian invasion of Ukraine. (Photo by Dimitar Dilkoff/AFP Photo)