The 1971 May Day Protests were a series of large-scale civil disobedience actions in Washington, D.C., in protest against the Vietnam War. These began on May Day of that year, continued with similar intensity into the morning of the third day, then rapidly diminished through several following days.

Members of the Nixon Administration would come to view the events as damaging, because the government's response led to mass arrests and were perceived as violating rights.

By the middle of 1970 many leaders of the anti war movement had come to believe that tactics of massive, non-violent political protests that had been used previously would not end the war, and that more aggressive actions were needed. Rennie Davis and Jerry Coffin of the War Resisters League began planning the actions; later in 1970 Michael Lerner joined their number. The May Day tribe was formed. It was made up of Yippies and others among the more militant members of the anti-war movement. It was decided that small groups of protesters would block major intersections and bridges in the capital.

35,000 protesters camped out in West Potomac Park near the Washington Monument park to listen to rock music and plan for the coming action. The government planned to use low flying helicopters to disrupt the protest. This tactic was stymied by the launching of large numbers of helium filled balloons - some of which were tethered by cables large enough to snarl a helicopter's rotors.

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