“Should a professor of accounting or chemistry be fired for using up class time to sound off about homelessness or the war in Iraq? Yes! There is no high moral principle that prevents it. What prevents it are tenure rules that have saddled so many colleges with so many self-indulgent prima donnas who seem to think that they are philosopher kings, when in fact they are often grossly ignorant or misinformed outside the narrow confines of their particular specialty.”