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
CIA activities in Vietnam Vietnam to treat refugees and to train Vietnamese medical personnel. The second pacification operation was launched late April 1955 in the southern Dinh Dinh and northern Phu Yen portion of Central Vietnam. Northern Vietnamese troops needed a way to link themselves with their allies in Southern Vietnam. The Viet Cong and Northern Vietnamese soldiers were able to supply troops and military operations through secret tunnels and the Ho Chi Minh trail. The Ho Chi Minh trail was an interlocking trail system that was created through the borders of Laos and Cambodia that reach from North Vietnam to South Vietnam. During