Germany sunk the U.S. ship “Lusitania”. It had enforced a strict,” unrestricted submarine warfare” and sunk all ships in the Atlantic ocean. It moved the U.S. towards war because this was an attack on a civilian ship. There was a large amount of American citizens close to around 130 people. This incident as well as the Zimmerman Telegram marched the United States into war against the Triple Alliance. It entered with it’s allies the Triple Ententé.