It increased the American public's support of war against Germany.
Explanation:
The loss of civilian lives led many Americans to support involvement in the conflict. The Lusitania was a luxury cruise ship of America that was carrying almost 3046 passengers and crew to England.
When the ship was approaching the island of Ireland, it was attacked by the Germans. Germany has already warned America that it would attack any ship that traveled to England because Germany was using submarines and had already declared the seas around Britain a war zone.
When the submarine also known as U-boat released that a ship had entered the war zone it attacked the Lusitania which began to sink immediately and resulted in the loss of 1198 lives.