What the names of two rock legends that passed away in the early 70s?

 Janis Joplin and Jim Morrison

Explanation:  Janis Joplin (1943 - 1970), American rock and blues singer, distinctly sharp and distinctive voice, with extraordinary vocal abilities. Especially popular during the hippie movement during the 60's of the 20th century. One of the most famous versions of the work she performed was Summertime.

Jim Morrison (1943 - 1971), an American singer, poet and leader of the band The Doors. Known for its performances and an extremely melancholic voice, according to critics, one of the most authentic pop icons of modern music of the 20th century.

to contain the wave of communism

yes

explanation:

the fighting words doctrine, in united states constitutional law, is a limitation to freedom of speech as protected by the first amendment to the united states constitution. in 1942, the u.s. supreme court established the doctrine by a 9–0 decision in chaplinsky v. new hampshire.