Turning Point of U.S. Involvement in Vietnam War

During the Vietnam War, the United States faced significant challenges both on the battlefield and at home. One of the primary reasons for U.S. involvement in Vietnam was the government's desire to prevent the spread of communism in Southeast Asia. This period saw a massive escalation of military engagement and protests against the war.

Which event, occurring in 1964, is often cited as a major turning point that led to increased U.S. military presence in Vietnam?