...is "we tried that, it didn't work, and now they're just telling us we needed more in the first place - you can't win if the response is always 'well if we did more it would work'."
You hear this a lot - it's either ignorant or disingenuous - and either way it's a really, really bad case against stimulus advocates.
Paul Krugman explains in detail why here. As he says here, this is not some ex post rationalization. The stimulus argument was laid out in detail before Obama took office. I don't know of any economist (there are probably some, but I'm not aware of any) not working for the government that thought the $800K stimulus was a good figure. Independent economists either said it was too small or that it should have been $0. Even some administration economists, such as Christie Romer, apparently thought it was too small as well, but was silenced by poilticos. But I am not personally aware of an independent economist that thought it was right (maybe a few economic journalists, but since when do they run the numbers?).
If you're going to take issue with fiscal stimulus, make the argument on the merits - don't dredge up some ridiculous and easily debunked argument that advocates are just rationalizing after the fact, or that we didn't see this coming.
Krugman of course makes a mistake himself in this blog post - he only mentions the federal government. It looked like we needed about $2 trillion in stimulus, but that means $2 trillion in net stimulus. If the states are working against the feds, that shrinks the actual amount of fiscal stimulus even further.
It seems to me this recession offers a case study in do-nothing or at least do-very-little policy. If you're not happy with the policy response either, I can understand that. But at least be aware enough of your opponents views to recognize why this has been such a disappointment.
It would be a good reason to turn on Obama, in fact, if I thought anyone else out there would have done a better job - but unfortunately this is probably the best we could have hoped for. Don Boudreaux often chimes in on statements like that and says "well why do you want to give power to people that are so disappointing to you". I would think the answer to that question would have been obvious - because minimal fiscal stimulus is better than no fiscal stimulus. Disappointing action on the part of policy makers doesn't imply at all that no action on the part of policy makers is better.
UPDATE: Apparently Krugman tapped into a concern that a lot of people share. Brad DeLong just reposted this too. It's really hard to emphasize enough how dumb some people sound when they attack stimulus advocates from this angle.
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