Digby has some commentary on the right-wing crusade against "liberal professors". The real problem, though, is that the professor in question was a bad professor who also happened to be liberal. When David Horowitz or whoever trots out these examples, he is of course trying to conflate the two categories to score political points, but he's also obscuring the more important issue, which is poor-quality teaching. That sleight-of-hand is the only reason Horowitz and co. are getting any traction on this.