I think I finally get why his economist opponents and detractors pain him so much, eliciting observations on their foolishness like this one:
The ones who set Krugman off are not those who are just whores, academics whose "learning" simply amounts to apologies for rich people stealing from everyone else.
His greater objects of scorn are another sort of "expert" who has come to believe that the object of the economics is the well-being of an abstraction called "the economy." Krugman manipulates data with the best of them, but he never forgets that "the economy" is exists for the well-being of the people whose activity (and inactivity) is the economy. This puts him out of step with too many of his peers.