A South Korean soldier wear North Korea's military uniform, acting as North Korean soldier during an anti-terror and anti-chemical drill session held as part of the 2011 Ulchi Freedom Guardian (UFG) event on August 17, 2011 in Seoul, South Korea. The 11-day UGC, which features drills including the handling of chemical and biological attacks, is a regular joint exercise between US and South Korean troops to prepare for potential emergencies on the Korean Peninsula. (Photo by Chung Sung-Jun/Getty Images)

Iraqi soldiers from 9th Armoured Division give drops of water to a dehydrated child rescued earlier by soldiers at the frontline, during the ongoing fighting between Iraqi forces and Islamic State militants near the Old City in western Mosul, Iraq June 13, 2017. (Photo by Erik De Castro/Reuters)

The faces of war have been brought back to life after a series of World War One photographs were expertly colourised. The black and white snaps were painstakingly restored and colourised by photographer Mario Unger (53) from Rotenturm, Austria. Here: One image shows an unidentified American soldier posing with a pistol, helmet, and Iron Cross medal taken from a German soldier, 1918. (Photo by Mario Unger/Mediadrumworld)

Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)

A Thai Buddhist monk prepares to take part in a televised anti-plague prayer at Wat Traimit Temple (Temple of the Golden Buddha) amid lockdown restrictions to contain the spread of the COVID-19 coronavirus in Bangkok on March 25, 2020. The monks at Buddhist temples nationwide chanted the Rattanasoot (Seven Legends) Prayer in unison in a bid to boost public morale amid the epidemic of COVID-19 coronavirus. (Photo by Mladen Antonov/AFP Photo)

People assist a woman who was exposed to tear gas by pouring milk over her face after police fired tear gas and water canon to try and disperse protesters outside Parliament on November 17, 2020 in Bangkok, Thailand. The demonstrators gathered outside parliament, on Tuesday, as the Thai government met to discuss amendments to the country's constitution. (Photo by Lauren DeCicca/Getty Images)

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)