An ethnic Armenian fighter carries Kalashnikov machine guns to his comrade-in-arms at Martakert province in the separatist region of Nagorno-Karabakh, Azerbaijan, Monday, April 4, 2016. (Photo by Vahan Stepanyan/PAN Photo via AP Photo)

An Israeli soldier from the Nahal Infantry Brigade runs through smoke released from a smoke grenade during an urban warfare drill near an abandoned hotel in Arad, southern Israel February 8, 2017. (Photo by Amir Cohen/Reuters)

A U.S. Marine leads training on a shooting range in France in an undated photo taken during the First World War. (Photo by Reuters/Courtesy Library of Congress)

Indian policemen carry the body of one of their colleagues killed in a rebel attack in the town of Dinanagar, in the northern state of Punjab, India, Monday, July 27, 2015. Indian forces fought an extended gunbattle Monday with militants who attacked a moving bus and stormed into a police station in a northern town bordering Pakistan. (Photo by Channi Anand/AP Photo)

Three Chinese soldiers at the time of a civil war in China. (Photo by General Photographic Agency/Getty Images). 1922

Bicycle rickshaw drivers chat as they wait for customers near the Drum Tower in a traditional neighbourhood on September 30, 2021 in Beijing, China. China will mark National Day and the Golden Week holiday from October 1st. (Photo by Kevin Frayer/Getty Images)

Members of an American landing party assist troops whose landing craft was sunk by enemy fire off Omaha beach, near Colleville sur Mer, France, June 6, 1944. REUTERS/Weintraub/US National Archives

People wearing and holding helmets take part in a drill simulating a 7.2 magnitude earthquake in Tokyo, Japan, August 26, 2016. The drill was held in Ginza, a high-end shopping and business district, and held ahead of the 93rd anniversary of the Great Kanto Earthquake of 1923 which claimed at least 100,000 casualties. It was one of the largest natural disasters in recorded history and since 1960, September 1st, and the period around that date has been declared as national disaster prevention awareness period. (Photo by Kim Kyung-Hoon/Reuters)