"The price of lawful public dissent must not be a dread of subjection to an unchecked surveillance power. Nor must the fear of unauthorized official eavesdropping deter vigorous citizen dissent and discussion of Government action in private conversation. For private dissent, no less than open public discourse, is essential to our free society.
As nightfall does not come all at once, neither does oppression. In both instances, there is a twilight when everything remains seemingly unchanged. And it is in such a twilight that we all must be aware of change in the air, however slight, lest we become unwilling victims of the darkness."
~Justice William O. Douglas~