7日エントリで紹介した税負担の問題について、ケビン・ハセットCEA委員長がTax Policy Centerで講演したのに対し、クルーグマンがトンデモ経済学だと批判している。その上で、危機後にそうしたトンデモ経済学が生み出された過程を以下のように説明している。

When the financial crisis struck, there were many calls for new economic ideas – even an Institute for New Economic Thinking. The implicit story, pretty much taken for granted as true, was that the crisis proved the inadequacy of economic orthodoxy and the need for fundamental new concepts. Pretty obviously, too, supporters of calls for new thinking had a sort of Hollywood script version of how it would play out: daring innovators would propose radical ideas, would face resistance from old fuddy-duddies, but would eventually win out through their superior ability to predict events.
What actually happened was very different. True, nobody saw the crisis coming. But that wasn’t because orthodoxy had no room for such a thing – on the contrary, panics and bank runs are an old topic, discussed in every principles book. The reason nobody saw this coming was an empirical failure – few realized that the rise of shadow banking had done an end run around Depression-era bank safeguards.
The point was that only the dimmest of free-market ideologues reacted with utter bewilderment. The rest of us slapped our foreheads and said, “Diamond-Dybvig! How stupid of me! Diamond-Dybvig!”
重要なのは、完全に当惑したのは自由市場イデオローグの中で最も愚鈍な者たちだけだった、という点である。残りの者は、額を叩いてこう言った。「ダイアモンド=ダイビックだ! それに気付かなかったなんて! ダイアモンド=ダイビックだよ!」


And post-crisis, pretty standard macro worked pretty well. Both fiscal policy and monetary policy did what they were supposed to (or, in the case of money, didn’t do what they weren’t supposed to) at the zero lower bound. Plenty of room for refinement, lots of opportunities to use the mother of all natural experiments for empirical work, but no huge requirement for radical new thinking.
Nonetheless, there was a proliferation of radical new concepts: contractionary fiscal policy is actually expansionary, expansionary monetary policy is actually deflationary, terrible things happen to growth when debt crosses 90 percent of GDP. These ideas instantly got huge amounts of political traction – never mind the fuddy-duddies in the economics establishment, the policy establishment leaped at the chance to apply new ideas.
What did the ideas they leaped at have in common? All of them had, implicitly or explicitly, conservative ideological implications, whether the authors intended that or not. (I’m quite sure that Reinhart-Rogoff weren’t operating out of any political agenda. Not equally sure about others.) And all of them proved, quite quickly, to be dead wrong.
So new economic thinking since the crisis has proved, for the most part, to consist of bad ideas that serve a conservative political agenda. Not exactly the script we were promised, is it?
彼らが飛びついた考えの共通項は何だったのだろうか? それらすべては、暗黙裡もしくは明示的に、著者たちが意図していたにせよ意図していなかったにせよ、保守的な思想を含意していた(ラインハート=ロゴフに政治的な思惑は無かった、ということを私は確信している。他の連中についてはそれほどの確信は無い)。それらすべては、完全に間違っていることがすぐに明らかになった。


Once you think about it, it’s not too hard to see how that happened. First of all, conventional macro has worked pretty well, so you’d need really, really brilliant innovations to make a persuasive major break with that conventionality. And really, really brilliant innovations don’t come easy. Instead, the breaks with conventional wisdom came mainly from people who, far from transcending that wisdom, simply failed to understand it in the first place.
And while there are such people on both left and right, there’s a huge asymmetry in wealth and influence between the two sides. Confused views on the left get some followers, provoke a back-and-forth on a few blogs, and generate some nasty tweets. Confused views on the right get mainlined straight into policy pronouncements by the European Commission and the leadership of the Republican Party.