Economist and New York Times columnist Paul Krugman, the hero of liberals everywhere, did a year-end interview posted Monday with Ezra Klein of Vox. Clearly, he must have been in a slyly silly mood as he told Klein that Times readers would have "no idea with party I favor in general elections."

EZRA KLEIN: What do you think about the argument that’s playing out on the left between the vision of the Democratic Party represented by Hillary Clinton and the vision represented by Elizabeth Warren? Do you think they’re that different?

PAUL KRUGMAN: I would say at this point it looks mostly like symbolism. Among liberals in America, there’s actually fairly widespread dismay over actually what I think of as Clinton-Blairism; the kind of ‘90s liberalism that is not really taking on economic inequality, not really taking on Wall Street. And there’s a sense that Hillary Clinton might be a return to that.

But I don’t think Hillary Clinton is going to try and make it 1999 again. I remember in 2008 — as a Times columnist, I can't do endorsements, so you have no idea which party I favor in general elections — but I was skeptical of Obama at a time when a lot of people on the Left were very, very high on him. I heard a number of people saying, oh, god, if Hillary is elected, she's going to bring in the old Rubin crowd, people like Larry Summers, to run the economy. And then Obama got elected and did exactly that. I think, if anything, he was more conventional on economics than she was.

I think at this point, Elizabeth Warren is now the visible embodiment of the wing of the Democratic Party that’s determined not to return to Clinton-Blairism. That makes her useful even if she doesn’t run, as — I don't know — a ghost or something looming over Hillary.