Tyler Cowen asks "Which 20th century classic of American conservative political thought has held up best?" This isn't to ask which is your favorite, or which most influenced you, but which has held up the best. "Road to Serfdom is a contender," he writes, "even though its main empirical point (socialism leads to loss of political freedom) would seem to be refuted." If you have ideas on this score, head over to his place and share them. But for now, I'd ask the same about 20th century classics in liberal political thought. Unlike Tyler, I'm not going to disallow economics-texts, largely because I think Galbraith should be part of the discussion. Rawls would seem an obvious contender, as would Susan Moller Okin. But range widely.