Vernon Bogdanor has an important piece on the reasons for this in this week’s New Statesman. His argument is that the bureaucratisation of the education system and the emphasis that the research assessment exercise puts on the rapid production of research has led to an emphasis on an intellectually uninteresting scholasticism in the social sciences. Bogdanor believes that the way to get the universities contributing usefully to policy debates is to free them up from government control, to let them become more independent and therefore intellectually creative.
PS Bogdanor also relays this striking anecdote about the power of ideas:
“A group of French aristocrats, so it is said, were seen chuckling over the first edition of Rousseau's Du contrat social. The second edition was bound with their skins.”