 Sidney Hook’s emergence as a major American philosopher and his accompanying prominence as an influential intellectual in the American cultural and political scene took place during the decades of the 1930s and 40s. During that period he was recognized as a forceful defender of pragmatic theses in theory of knowledge and ethical theory. Yet the greatest part of Hook’s oeuvre is comprised of writings on the issues that were brought into focus within American social and political thought in the post-War period. As a political philosopher, Hook had been involved from the outset of his career in the fundamental issues of democracy, liberty and equality. In the post-War period, however, Hook was embroiled in political controversy over the balance between individual liberty and national security occasioned by the exigencies of the Cold War. Hook’s support for a balance which recognized the need for limitations of liberty for the sake of national security led him to a critique of the dominant liberal position which argued against new executive or legislative efforts to enhance national security that could requires any limitation of individual liberty. On Hook’s view, the traditional liberal position of the Millian variety represented a form of what he termed “ritualistic liberalism.”