Angered by the radical politics of the 1960s, and especially by the student occupation and temporary closure of Columbia University in 1968, Hofstadter began to criticize student activist methods. His friend David Herbert Donald said, "as a liberal who criticized the liberal tradition from within, he was appalled by the growing radical, even revolutionary, sentiment that he sensed among his colleagues and his students. He could never share their simplistic, moralistic approach." Brick says he regarded them as "simple-minded, moralistic, ruthless, and destructive." Moreover, he was "extremely critical of student tactics, believing that they were based on irrational romantic ideas, rather than sensible plans for achievable change, that they undermined the unique status of the university, as an institutional bastion of free thought, and that they were bound to provoke a political reaction from the right." Coates argues that his career saw a steady move from left to right, and that his 1968 Columbia commencement address "represented the completion of his conversion to conservatism".