An Iraqi special forces soldier shot dead an Islamic State suicide bomber in Mosul, Iraq March 3, 2017. (Photo by Goran Tomasevic/Reuters)

Russian soldiers write home while serving on the Eastern Front during World War I, circa 1915. (Photo by Hulton Archive/Getty Images)

Israeli soldiers get ready to launch the Skylark drone during a drill on January 16, 2012 near Bat Shlomo, Israel. (Photo by Uriel Sinai/Getty Images)

Taliban soldiers ride bumper cars at an amusement park in Kabul, Afghanistan on September 13, 2021. (Photo by WANA via Reuters)

Figure Skating, ISU Grand Prix of Figure Skating NHK Trophy 2016/2017, Ice Dance Short Dance, Sapporo, Japan on November 26, 2016. Kaitlin Hawayek and Jean-Luc Baker of the U.S. compete. (Photo by Issei Kato/Reuters)

Journalists interview a girl, member of the Cryophile amateurs winter swimmers club, after bathing in the ice waters of the Yenisei River, during the celebrations for the upcoming Christmas and New Year, in Krasnoyarsk, Russia, December 23, 2017. (Photo by Ilya Naymushin/Reuters)

Women wearing "Shiroshozoku" or the traditional white robe pray as they bathe in ice-cold water at the Teppozu Inari shrine in Tokyo, Japan, January 10, 2016. About 100 participants took part in the Shinto ceremony to purify their souls and wish for good health in the new year. (Photo by Yuya Shino/Reuters)

Tourists ice skate at night on the Eiffel Tower's skating rink in Paris December 9, 2014. The skating rink, located on the first level of the Eiffel Tower, opens to the public as part of the Christmas holiday season. (Photo by Charles Platiau/Reuters)