Krugman Nails It on NAIRU

I generally agree with Paul Krugman in his arguments on macro policy, but sometimes it is worth emphasizing a point of agreement. Krugman really nails the issue today in discussing the Fed's approach to tightening.

The question is at what point should the Fed start raising interest rates to keep the unemployment rate from falling further. The concern is that if unemployment gets too low, the inflation rate would start to accelerate. Krugman points out that we really don't know the level of u...