Whatever the cause, the fact is that there is a sharp trade-off between democracy and good economic policy-making.And I agree.
But I'm willing to bet that while most economists would agree with Chris's diagram they would not agree on what goes into the left hand side of the figure. My view of "policies which are good" is likely to be very different from Chris's view of good policy. But, interestingly, we would both see our favoured policies, whatever they are, as unpopular. Which raises the question if all "good economic policies" are unpopular can we ever get anyone's version of good policy implemented? Does politics gut all economic policy, no matter whether "left" or "right", of all serious content? Are we doomed by the populist nature of politics to get crap economic policy no matter how we define good policy?