How did the United States' decision to join the Allies affect World War I?

2 Answers
May 14, 2017

It helped make the defeat of Germany possible

Explanation:

In 1917 after the Bolshevik Revolution, Russia signed the Brest-Litovsk separate peace treatyand withdrew from the war. The fact that the USA joined the war counterbalanced this loss of an ally.

May 15, 2017

The United States joining World War I prevented the Allies defeat by Germany.

Explanation:

In April 1918 The Germans started ts he Spring Offensive using 50 divisions that had been released from the Eastern Front due to the treaty of Brest-Litovsk with Russia. Russia had withdrawn from the war freeing these troops to fight on the Western Front.

The spring offensive used a new technique of storm troopers to infiltrate the allied lines. The Germans were attempting to split the British and French units to force the French to sign a peace treaty.
American units faced battle for the first time in April 20 1918. The American units were instrumental in preventing a decisive German breakthrough in the April offensive.

In May 27 the German's launched another offensive that crossed the Marne River threatening Paris. Only a massive counter offensive by a combined French and American units prevented the German forces from capturing Paris and winning the war.

by July 15 the Germans had 207 divisions to 203 Allied divisions. The French were discouraged and demoralized and their troops threatening to mutiny. 2 million fresh American troops changed the balance of the war. In August an allied counter offensive American forces operated in independent formations. These forces used new techniques pushing back the German lines.

By the end of August the German lines collapsed and Germany surrendered.

The United States decision to join World War I prevented the defeat of the Allied forces in April, May and July of 1918. In August the influx of 2 million fresh American troops led to the collapse and defeat of the German forces. Without the American troops the Allies would most likely have lost the war.