The launch of the Tet Offensive by North Vietnamese communist troops in January 1968, and its success against U.S. and South Vietnamese troops, sent waves of shock and discontent across the home front and sparked the most intense period of anti-war protests to date. By early February 1968, a Gallup poll showed only 35 percent of the population approved of Johnson’s handling of the war and a full 50 percent disapproved (the rest had no opinion). Joining the anti-war demonstrations by this time were members of the organization Vietnam Veterans Against the War, many of whom were in wheelchairs and on crutches. The sight of these men on television throwing away the medals they had won during the war did much to win people over to the anti-war cause.
After many New Hampshire primary voters rallied behind the anti-war Democrat Eugene McCarthy, Johnson announced that he would not seek reelection. Vice President Hubert Humphrey accepted the Democratic nomination in August in Chicago, and 10,000 anti-war demonstrators showed up outside the convention building, clashing with security forces assembled by Mayor Richard Daley. Humphrey lost the 1968 presidential election to Richard M. Nixon, who promised in his campaign to restore “law and order”–a reference to conflict over anti-war protests as well as the rioting that followed King’s assassination in 1968–more effectively than Johnson had.
The following year, Nixon claimed in a famous speech that anti-war protesters constituted a small–albeit vocal–minority that should not be allowed to drown out the “silent majority” of Americans. Nixon’s war policies divided the nation still further, however: In December 1969, the government instituted the first U.S. draft lottery since World War II, inciting a vast amount of controversy and causing many young men to flee to Canada to avoid conscription. Tensions ran higher than ever, spurred on by mass demonstrations and incidents of official violence such those at Kent State in May 1970, when National Guard troops shot into a group of protesters demonstrating against the U.S. invasion of Cambodia, killing four students.
In mid-1971, the publication of the first Pentagon Papers–which revealed previously confidential details about the war’s conduct–caused more and more Americans to question the accountability of the U.S. government and military establishments. In response to a strong anti-war mandate, Nixon announced the effective end to U.S. involvement in Southeast Asia in January 1973.