In an attempt to keep derp from taking root, Noah Smith wrote a post on conservative economic arguments since the crisis, where he analyses a popular conservative position and sees how accurate it turned out.
After plowing through six argument, Noah (correctly) judges that the conservatives have an awful track record with economic predictions. Which is rather unfortunate for the country.
You should read the post in full.
I do however, think that Noah was a bit too nice in awarding 50% accuracy rating to the “deficits must be cut in the crisis” argument, as Europe’s brush with austerity has pretty conclusively shown deficit reduction to be a horrid idea in a crisis. But I suppose Noah wanted to throw conservatives a bone by looking further into the future, where after the economy has completely the conservative position of deficit reduction would be be in accordance to Keynesian fiscal policy,
Also, I might also be a bit more lenient on the conservatives with the “Fannie & Freddie cause the crisis” argument, since while they were not the causes of the crisis, the government had to bail them out.