First, from the Brad Delong article Krugman addresses in his piece:
J. Bradford DeLong
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Economists today know a great deal more – albeit not as much as we would like – about how monetary, banking, and fiscal policies affect the flow of nominal spending, and their findings are the topic of a great deal of open and deep political and public intellectual discussion. And the working classes all have the vote.
Thus, I would confidently lecture only three short years ago that the days when governments could stand back and let the business cycle wreak havoc were over in the rich world. No such government today, I said, could or would tolerate any prolonged period in which the unemployment rate was kissing 10% and inflation was quiescent without doing something major about it.
I was wrong. That is precisely what is happening.
How did we get here? How can the US have a large political movement – the Tea Party – pushing for the hardest of hard-money policies when there is no hard-money lobby with its wealth on the line? How is it that the unemployed, and those who fear they might be the next wave of unemployed, do not register to vote? Why are politicians not terrified of their displeasure?
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It is now clear that the right-wing opponents to the Obama administration’s policies are not objecting to the use of fiscal measures to stabilize nominal spending. They are, instead, objecting to the very idea that government should try to serve a stabilizing macroeconomic role.
morePaul Krugman
Brad DeLong writes of how our perception of history has changed in the wake of the Great Recession. We used to pity our grandfathers, who lacked both the knowledge and the compassion to fight the Great Depression effectively; now we see ourselves repeating all the old mistakes. I share his sentiments.
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Intellectual instabilityThe brand of economics I use in my daily work – the brand that I still consider by far the most reasonable approach out there – was largely established by Paul Samuelson back in 1948, when he published the first edition of his classic textbook. It’s an approach that combines the grand tradition of microeconomics, with its emphasis on how the invisible hand leads to generally desirable outcomes, with Keynesian macroeconomics, which emphasizes the way the economy can develop magneto trouble, requiring policy intervention. In the Samuelsonian synthesis, one must count on the government to ensure more or less full employment; only once that can be taken as given do the usual virtues of free markets come to the fore.
It’s a deeply reasonable approach – but it’s also intellectually unstable. For it requires some strategic inconsistency in how you think about the economy. When you’re doing micro, you assume rational individuals and rapidly clearing markets; when you’re doing macro, frictions and ad hoc behavioral assumptions are essential.
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And by the time that big shock arrived, the descent into an intellectual Dark Age combined with the rejection of policy activism on political grounds had left us unable to agree on a wider response.
In the end, then, the era of the Samuelsonian synthesis was, I fear, doomed to come to a nasty end. And the result is the wreckage we see all around us.