Vietnam ground combat operations in 1965, and at their peak they numbered more than 500,000. The US also engaged in a sustained aerial bombing campaign. Meanwhile, China and the Soviet Union provided North Vietnam with significant material aid and 15,000 combat advisers. Communist forces supplying the Việt Cộng carried supplies along the Hồ Chí Minh trail, which passed through the Kingdom of Laos. The communists attacked South Vietnamese targets during the 1968 Tết Offensive. Although the campaign failed militarily, it shocked the American establishment, and turned US public opinion against the war. During the offensive, communist troops massacred over 3,000 civilians
1964 in the Vietnam War and Vietnam's central highlands. Former President John F. Kennedy's brother, Robert Kennedy, said in an oral interview for the Kennedy Library that President Kennedy had "a strong, overwhelming reason for being in Vietnam and that we should win the war in Vietnam." Kennedy denied that any consideration had been given by the President to withdrawing from Vietnam. He equivocated on the introduction of U.S. ground troops into Vietnam, saying that "we'd face that when we came to it." Viet Cong commandos eluded detection and placed an explosive on the USS Card, an escort aircraft carrier of World War II vintage.