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)

A woman is having a massage at the Lukacs Bath in Budapest, Hungary June 28, 2016. Hungary's capital owes its popularity as a tourist destination partly to its numerous hot springs and bathing culture which have drawn visitors to the area since Roman times. Bath houses range from large, ornate 19th-century buildings like the Gellert and the Szechenyi to tiny Ottoman Turkish-era hamams, some of them more than 500 years old. (Photo by Bernadett Szabo/Reuters)

Vladislav Doronin and Naomi Campbell attend the religious ceremony of the Royal Wedding of Prince Albert II of Monaco to Princess Charlene of Monaco in the main courtyard at the Prince's Palace on July 2, 2011 in Monaco. The Roman-Catholic ceremony follows the civil wedding which was held in the Throne Room of the Prince's Palace of Monaco on July 1. With her marriage to the head of state of the Principality of Monaco, Charlene Wittstock has become Princess consort of Monaco and gains the title, Princess Charlene of Monaco. Celebrations including concerts and firework displays are being held across several days, attended by a guest list of global celebrities and heads of state. (Photo by Sean Gallup/Getty Images)

Soldiers take part in a drill during a heavy snow in Heihe, Heilongjiang province, February 26, 2014. (Photo by Reuters/China Daily)