What 2 German actions cause the us to enter World War 1?

Two key German actions that prompted the U.S. to enter World War I were unrestricted submarine warfare and the Zimmermann Telegram. Germany's resumption of unrestricted submarine warfare in early 1917 led to the sinking of American merchant ships, heightening tensions. Additionally, the interception of the Zimmermann Telegram, in which Germany proposed a military alliance with Mexico against the U.S., further inflamed public opinion and pushed the U.S. towards war.