Answer:
The USA, which has violated its neutrality by selling weapons to the Allied Powers since the beginning of the war, did not heed the warnings of Germany.
Due to the fact that the USA did not heed the warnings of Germany, on March 17, when German submarines opened fire on the American merchant fleets, the USA declared war on Germany and the USA entered the war.
Thereupon, the principles published by the President of the United States, Wilson, upset the balance in the Entente group.
