I worry that policy makers will just sit there, for years and years, all the while congratulating themselves on the soundness of their policies.

"And I worry that policy makers will just sit there, for years and years, all the while congratulating themselves on the soundness of their policies." As well you should. Try to come up with an example of the last time a complete policy failure actually resulted in a change of policy.

I can do that. Reagan tax cuts. Krugman has the right to be depressed.