What happened as a result of unrestricted submarine warfare of Lusitania?

The unrestricted submarine warfare employed by Germany during World War I led to the sinking of the RMS Lusitania on May 7, 1915, resulting in the deaths of 1,198 passengers, including 128 Americans. This incident heightened anti-German sentiment in the United States and contributed to the U.S. entering the war in 1917. The Lusitania's sinking also prompted Germany to reconsider its submarine warfare tactics, as it faced increased pressure from neutral nations.