Krugman acidly remarks in a blog post that some of the arguments against Keynesians like him are so bogus and malicious that: "You have to assume that this kind of argument is made in deliberate bad faith — although I suspect that many of these people don’t remember what it is to make an argument in good faith."
The argument in question was that when Krugman points out that WWII overcame the depression by massive spending he is being a war monger. Of course he is arguing for government spending on infrastructure, education, etc., not war.
I think what this points up is that Democrats should not only be answering the arguments of the RepubliCONs, but to point out their dishonesty. They are not interested in the truth, but only name-calling and belittling the opposition.