World War I was an industrialized war. Industry produced weapons with the same efficient mass production methods that it had applied to other products. One of the most important new weapons of World War I was the machine gun. Its sweeping, rapid-fire spray of bullets was deadly and often made infantry advances terribly costly. To protect themselves from the machine gun’s raking fire and from artillery bombardments, soldiers dug systems of trenches. Both sides used weapons that had never been tried before. In 1916 the British introduced the tank, an armored vehicle on which guns were mounted. Tanks enabled troops to tear through barbed wire and cross enemy lines. Another new weapon was the recently invented airplane. Airplanes were primarily used for observing troop movements.
Although early military airplanes were not very maneuverable or fast, they sometimes engaged in air battles called dogfights and dropped bombs. Germany became the first nation to make effective use of submarines. Its U-boats (from the German word Unterseebooten, meaning “underwater boats”) caused extensive losses to Allied shipping. The Germans also introduced poison gas. Previously in Europe, most wars were fought by professional soldiers whose only source of income was their military pay and rations. In contrast, armies of drafted civilians fought the battles of World War I. Those who could not fight worked at home to help the war effort. Many women participated by working in factories. A war in which nations turn all their resources to the war effort became known as “total war.”
To stir the patriotism of their people and support for the war effort, governments made wide use of propaganda-ideas, facts, or rumors spread deliberately to further one’s cause or to damage an opposing cause. Governments set up agencies to handle the flow of information about the war. Newspapers and popular magazines, especially those of the Allies, portrayed the enemy as brutal and subhuman, while praising their own national aims and achievements.