There's a new scarlet letter in town. Actually, it's the same letter -- "A" -- but it stands for a different word that's increasingly regarded as shameful: Austerity. The darling idea of 2010 and 2011 has become the pariah concept of 2012. And the evidence of profound change is all around, from France and Greece to Germany and -- gasp -- the Republican Party. The change, when it comes to the conventional wisdom on austerity, has come from a combination of public pressure and leadership: one pushing up from below, the other pressing down from above. None of this means that we should break out the Keynesian champagne any time soon. But it's clear the forces of austerity are in retreat. And that's a very good thing.