What's wrong with Paul Krugman?

His last editorial on the Democratic race was not comprehensible to me. I know he is a Hilary advocate and I have no problem with him using his column to argue in favor of her candidacy over Obama's, even at this late date. But his most recent column seems petty and holding Obama to a standard that he does not hold Hilary to. He criticizes Obama's criticism of economic policy over the last couple of decades, and takes him to task for lumping in the Clinton years (which he believes were pretty good). This despite her politicizing the San Francisco "bitter" remarks, which although not Obama's best political moment, seems mild in comparison. Well, if Krugman wants 4 more years of Republican presidency, he is doing a darn good job of trying to ensure it happens.