The Vietnam War intensified tensions of the Cold War as the U.S. sought to contain the spread of communism through flexible response and increasing military spending. The U.S. became involved in Vietnam to aid South Vietnam after the 1954 Geneva Accords divided the country. As U.S. involvement grew, they used tactics like search and destroy missions and defoliants while the Viet Cong employed guerilla warfare. By 1969, the U.S. was divided as the public turned against the war, especially after events like the Tet Offensive and My Lai Massacre undermined the perception that the U.S. was winning. Protests on college campuses against the draft escalated tensions further.