United States foughtdeclared untilwar on Germany in April 1917. Officially it was an independent power and did not join the war'sAllies. It made its major contributions in terms of supplies, raw material and money starting in 1917. American soldiers under General [[John J. Pershing]] arrived in large numbers on the [[Western Front]] in summer 1918. They played a major role until victory was endachieved on November 11, 1918. Before entering the war, the US had remained neutral, though the US had been an important supplier to Britain and other [[Allies of World War I|Allied powers]]. During the war, the US mobilized over 4,000,000 military personnel and suffered 110,000 deaths, including 43,000 due to the [[1918 flu pandemic|influenza pandemic]].<ref>http://virus.stanford.edu/uda/</ref> The war saw a dramatic expansion of the US government in an effort to harness the [[war effort]] and a significant increase in the size of the US military. After a slow start in mobilizing the American economy and manpower, by spring 1918 the U.S. was poised to play a decisive role in the conflict. Under the leadership of President [[Woodrow Wilson]] the war represented the climax of the [[Progressive Movement]] as it claimed to bring reform and democracy to the world.
