I know that some people find this hard to understand -- perhaps because they don’t want to understand -- but people like me have never claimed that fiscal expansion is always and everywhere the right policy, even in response to recession. Nor are other arguments, like the argument that falling wages reduce, not increase, unemployment, universal. All of the unorthodox policy recommendations and conclusions are contingent on the economy being in a liquidity trap, in which short-run nominal interest rates are up against the zero lower bound and can’t go lower. And liquidity-trap conditions are rare; in fact, they’ve only happened twice in US history. Unfortunately, we’re living in one of those episodes right now.
Hell, if he intends us to read "only" there after that "contingent" rather than, say, "primarily," then compared to Krugman I guess I really am a wild eyed socialist and the Krugman of the last ten years isn't so different, really, from the one fifteen years before. Just a nice moderate post-Friedmanian Keynesian who thinks clearly and writes well. Of course, in these days of "serious" loons drooling cannibal blood between prayer meetings anybody to the left of Attila is indistinguishable from Kropotkin, so why split hairs, I guess?