The American Civil Liberties Union (ACLU) is a leading nonprofit organization dedicated to defending and expanding civil liberties in the United States. Founded in 1920 during a period of heightened government repression—including the infamous Palmer Raids targeting political dissidents—the ACLU emerged to protect free speech, due process, equal protection, and privacy, especially for groups historically denied these rights[2][4]. Its mission is realized through litigation, legislation, public education, and community outreach, making it a pioneer in public interest law[2][4]. ## History and Founding The ACLU traces its roots to the National Civil Liberties Bureau (NCLB), established in 1917 to support conscientious objectors and anti-war activists during World War I[1][3]. In 1920, Roger Baldwin, Crystal Eastman, and others reorganized the NCLB into the ACLU, broadening its focus beyond wartime dissent to encompass a wide array of civil liberties issues[2][3]. From its inception, the ACLU positioned itself as a nonpartisan defender of constitutional rights, distinct from organizations focused on specific demographics or causes[3]. ## Key Achievements The ACLU has been at the forefront of nearly every major civil liberties battle in U.S. history. Early highlights include defending targets of the Palmer Raids, supporting labor organizers, and securing the release of activists imprisoned for antiwar views[5]. The organization gained national attention with the 1925 Scopes "Monkey" Trial, challenging bans on teaching evolution and spotlighting issues of academic freedom and church-state separation[5][6]. In the mid-20th century, the ACLU played a pivotal role in landmark Supreme Court cases, such as Brown v. Board of Education (1954), which ended school segregation, and Tinker v. Des Moines (1969), affirming students' free speech rights[5]. The ACLU also fought—though not always successfully—against the intern