[Soldier aiming rifle from behind barricade, Tai'erzhuang, Xuzhou front, China]

[Republican soldier holding a rifle, Rio Segre, Aragón Front, near Fraga, Spain]

[Soldier aiming rifle from behind barricade, Tai'erzhuang, Xuzhou front, China]

[Soldier aiming rifle from behind barricade, Tai'erzhuang, Xuzhou front, China]

[Soldier aiming rifle towards water from sand bunker, near Guangzhou, China]

[Soldier aiming rifle from behind barricade, Tai'erzhuang, Xuzhou front, China]

U.S. Infantry attacking machine gun nests with rifle and hand grenades. Meuse-Argonne.

[Republican soldiers lying on the ground aiming rifles, Santa Eulalia, Aragón front, Spain]