But we must not forget that in our country are evangelists and zealots of many different political, economic and religious persuasions whose fanatical conviction is that all thought is divinely classified into two kinds — that which is their own and that which is false and dangerous. Communists are not the only faction which would put us all in mental straitjackets.

Robert H. Jackson (1892-1954) US Supreme Court Justice (1941-54), lawyer, jurist, politician

American Communications Association v. Douds, 339 U.S. 382, 438 (1950) [concurrence and dissent]
    (Source)