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
1968 in the Vietnam War President Lyndon Johnson addresses the nation, announcing steps to limit the war in Vietnam and reporting his decision not to seek reelection. The speech announces the first in a series of limitations on US bombing, promising to halt these activities above the 20th parallel. United States Secretary of Defense Clark Clifford gets the President to authorize 24,500 more troops on an emergency basis, raising authorized strength to the Vietnam War's peak of 549,500, a figure never reached. Operation Toan Thang I was a US and ARVN operation conducted between 8 April 1968 and 31 May 1968. Toan Thang, or "Complete