Vietnam War: The House Un-American Activities Committee begins investigations of Americans who have aided the Viet Cong. The committee intends to introduce legislation making these activities illegal. Anti-war demonstrators disrupt the meeting and 50 people are arrested.

The House Committee on Un-American Activities (HCUA), popularly the House Un-American Activities Committee (HUAC), was an investigative committee of the United States House of Representatives, created in 1938 to investigate alleged disloyalty and subversive activities on the part of private citizens, public employees, and those organizations suspected of having communist ties. It became a standing (permanent) committee in 1946, and from 1969 onwards it was known as the House Committee on Internal Security. When the House abolished the committee in 1975, its functions were transferred to the House Judiciary Committee.

The Viet Cong (VC) was an epithet and umbrella term to refer to the communist-driven armed movement and united front organization in South Vietnam. It was formally organized as and led by the National Liberation Front of South Vietnam, and conducted military operations under the name of the Liberation Army of South Vietnam (LASV). The movement fought under the direction of North Vietnam against the South Vietnamese and United States governments during the Vietnam War. The organization had both guerrilla and regular army units, as well as a network of cadres who organized and mobilized peasants in the territory the VC controlled. During the war, communist fighters and some anti-war activists claimed that the VC was an insurgency indigenous to the South that represented the legitimate rights of people in South Vietnam, while the U.S. and South Vietnamese governments portrayed the group as a tool of North Vietnam. It was later conceded by the modern Vietnamese communist leadership that the movement was actually under the North Vietnamese political and military leadership, aiming to unify Vietnam under a single banner.