Which was not directly related to the entry of the United states into world war 1?

The sinking of the Lusitania in 1915, while a significant event that heightened tensions between the United States and Germany, was not the direct cause of the U.S. entry into World War I. Instead, the direct catalyst was the interception of the Zimmermann Telegram in early 1917, in which Germany proposed a military alliance with Mexico against the U.S. Additionally, ongoing unrestricted submarine warfare by Germany played a crucial role in prompting the U.S. to declare war in April 1917.