"The danger to political dissent is acute where the Government attempts to act under so vague a concept as the power to protect 'domestic security.' Given the difficulty of defining the domestic security interest, the danger of abuse in acting to protect that interest becomes apparent."
This is a quote from the Supreme Court that Ashcroft's Department of Justice tried to censor out of an ACLU filing.
More at thememoryhole.org
Link found at supergee