The North Vietnamese launched the Tet Offensive in January 1968, attacking cities across South Vietnam in an attempt to spark uprising. Although the offensive was a military failure that inflicted heavy losses, it undermined the U.S. public's confidence in the war by showing the vulnerability of U.S. forces. This psychological victory for North Vietnam gave momentum to growing anti-war protests in the U.S. and prompted questions about the relevance of continued American involvement in the war.