The Vietnam War took a turn for the worse in 1963-1964. Both President Kennedy and South Vietnam's President Diem were assassinated, and a string of
Viet Cong victories turned the war's momentum decidedly in the communist force's favor. The United States was not fully committed to fighting the war, but refused to walk away from it, either.
Jan. 3, 1963- Battle of Ap Bac; 350 Viet Cong defeat much larger Southern force
May-Aug., 1963- Anti-Diem demonstrations; first Buddhist monk's self-immolation
Nov. 1, 1963- Assassination of President Diem, with hesitant U.S. approval
Nov. 22, 1963- Assassination of President Kennedy; Johnson vows to fight on
Dec. 31, 1963- 16,300 U.S. military advisors in South Vietnam by year's end
March 1964- Secret U.S. bombing of Ho Chi Minh Trail in Laos begins
May 4, 1964- International community imposes trade embargo on North Vietnam
Summer 1964- 56,000 Viet Cong reinforced by N. Vietnam regulars sweep south
June 20, 1964- Gen. William Westmoreland appointed to head U.S. forces