Question

Why did the United States come into the war on the Allied Side?

(Choose one):

1) German troops mistreated prisoners in Belgium.

2) Germany's policy of unrestricted submarine warfare made it necessary.

3) Austria-Hungary banned the import of American goods.

4) Its treaty obligation to Britain had to be upheld.

Answer 1

2.) Germany's policy of unrestricted submarine warfare made it necessary.

Step-by-step explanation:

Germany caused many civilian and military casualties due to unrestricted submarine warfare. America declared war on Germany and joined "the war to end all wars."