Construction workers attacked students and others who were protesting the Vietnam War in New York City.

The Hard Hat Riot occurred in New York City on May 8, 1970, when around 400 construction workers and around 800 office workers attacked around 1,000 demonstrators affiliated with the student strike of 1970. The students were protesting the May 4 Kent State shootings and the Vietnam War, following the April 30 announcement by President Richard Nixon of the U.S. invasion of neutral Cambodia. Some construction workers carried U.S. flags and chanted, "USA, All the way" and "America, love it or leave it." Anti-war protesters shouted, “Peace now."

The nationwide student anti-war strike of 1970 was a massive outpouring of anti-Vietnam War protests that erupted in May of 1970 in response to the expansion of the war into neighboring Cambodia. The strike began on May 1 with walk-outs from college and high school classrooms on nearly 900 campuses across the United States. It increased dramatically following the shooting of students at Kent State University in Ohio by National Guardsmen on May 4. While a number of violent incidents occurred during the protests, for the most part, they were peaceful.