The Fed caused the Great Recession with a tight money policy

See Don’t waste time looking for Ratex alternatives by Scott Sumner. Excerpt:

"Noah Smith has a new post discussing the current fad of looking for alternatives to the rational expectations model.  The motivation seems to be that we need to explain the collapse of bubble expectations and the rise in the propensity to save (although not actual saving?) during the 2008 recession.  I understand why people want to do this, but it would be a very big mistake.

I’ve always thought that it was patently obvious that the Fed caused the Great Recession with a tight money policy that allowed NGDP expectations to collapse in late 2008. But other people apparently don’t see it as being at all obvious.  They look for alternative explanations.  And yet when you ask them why, they tend to give these really lame “concrete steppes” explanations, such as, “The Fed didn’t raise interest rates on the eve of the Great Recession, so how can you claim that tight money caused the recession?”  Or they show themselves to be completely ignorant of actual Fed policy, and claim that the fed funds target was at zero when NGDP expectations collapsed in 2008.  It wasn’t.

Fortunately, neither of those apply to the ECB, which had positive target interest rates throughout 2007-2012, and which took “concrete steppes” in both 2008 and 2011, tightening money and triggering not one but two plunges in NGDP growth, which led to two recessions.  If there has ever been a more perfect example of the monetary policy/AS/AD model that we teach in our textbooks, I’d like to see it. (OK, maybe 1929-32.) And yet last time I did one of these rants almost no economists were blaming the ECB’s tight money policy for the double dip recession."