https://www.facinghistory.org/holoca...es-world-war-i
August 1914, both sides expected a quick victory. Neither leaders nor civilians from warring nations were prepared for the length and brutality of the war, which took the lives of millions by its end in 1918. The loss of life was greater than in any previous war in history, in part because militaries were using new technologies, including tanks, airplanes, submarines, machine guns, modern artillery, flamethrowers, and poison gas.
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