The correct answer to this open question is the following.
The Red Scare prompted the formation of the American Civil Liberties Union (ACLU) because American citizens were afraid that freedom and many liberties in the United States were being threatened by Communism.
The American Civil Liberties Union (ACLU) was formed in 1920 with the goal of defending individual liberties and rights granted by the US Constitution. The Red Scare created in Americans a sense of paranoia that demanded persecution of any suspect that professed Communist ideas.
Being a nonprofit organization, ACLU receives support from many groups and citizens to support the litigation and lobbying work with legislators and government officials.
