While it made elimination of enemies more quickly, it actually prolonged the war.
Machine guns used a link chain that passed through the gun chamber and fired at an extreme rate. By WWI, the main gun was based off of the Vickers machine gun, which was extremely more moblie and had a faster rate of fire than the weapon previously (Gatling gun in the American Civil War).
Barbed wire had a lesser impact, as they allowed the slowing of movements of troops early in the war, but with the technological advancement of tanks and the such, the role of barbed wire dropped, though it was still used extensively throughout the European front.
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