Why did the united states become involved in world war one?

Answer: The U. S. entered World War I because Germany embarked on a deadly gamble. Germany sank many American merchant ships around the British Isles which prompted the American entry into the war.

Sinking of American merchant ships

Explanation:

In early 1917 Berlin forced the issue. Its declared decision on 31 January 1917 to target neutral shipping in a designated war-zone became the immediate cause of the entry of the United States into the war. Five American merchant ships went down in March.