"In my judgment the people of no nation can lose their liberty so long as a Bill of Rights like ours survives and its basic purposes are conscientiously interpreted, enforced and respected so as to afford continuous protection against old, as well as new, devices and practices which might thwart those purposes. I fear to see the consequences of the Court's practice of substituting its own concepts of decency and fundamental justice for the language of the Bill of Rights as its point of departure in interpreting and enforcing that Bill of Rights."