Columbia subject headings:
Communism--United States
Communism--United States.
Persecution.
Subversive activities--United States.
Harvard subject headings:
Communism--United States
Communism--United States--1917-
Persecution
Subversive activities--United States
Princeton subject headings:
Communism--United States--1917-.
Persecution.
Subversive activities--United States.