Mary and Malcolm,

Obviously you are right that there were economists who advocated positions far from the wooden conception of laissez faire that Krugman is attributing to be dominant.

But let me push the point a minute ... isn't there something of a core proposition in "economics" which is related to the "harmony of interests" that comes down from Adam Smith thru Say and Bastiat and to the early neoclassical price theorists --- the market economy reconciles competing interests through exchange relations.  That "belief" came to represent in the public imagination what it meant to be an "economist". Those who argued that the market failed to reconcile interests and instead produced conflicts and tensions through monopoly, recurring cycles, income inequality, etc. were considered "unorthodox" economists.  Keynes seems to make this sort of claim in the General Theory --- that orthodox economists believed in market self-correction whereas unorthodox economist believed in distortions (general gluts, etc.).

Could this be what Krugman is picking up on?  A sort of distinction between "mainline" of economic thought (invisible hand and harmony of interests) and "mainstream" of economic thought (whatever is currently scientifically popular) might be useful.  There are occasions when the mainline of economic argument is not the mainstream, and other times when it aligns.

Perhaps it is this sort of broad brush argument that Krugman was getting at for good or bad.

Pete Boettke