Joe Biden and Elizabeth Warren have a long-running disagreement that dates back to the early 2000s when he was a senator championing a bill that would make it harder for people in bankruptcy to relieve themselves of certain debts, and she was a Harvard law professor crusading to make bankruptcy laws less brutal on people who fell on hard times.

When you watch Biden question her at a hearing in that old video, you can see in him a grudging respect laced with some barely contained anger. Though I can’t say for sure, it may have been because she not only had the better of the facts and arguments, but she also was advocating for ordinary people against big corporations, and Biden never wanted anyone to be more the champion of reg’lar folks than him. Even if, as the senator from Delaware, he often worked for the interests of the banks and credit card companies that make his state home.

That’s the critical context to an interesting back-and-forth the two candidates are having now, one that I think reveals something important about both of them but especially about Biden.

It started when Warren reacted to Biden’s criticism of her Medicare-for-all plan by saying he was “running in the wrong presidential primary” and “repeating Republican talking points.” This is a jab that is both quite common and pretty harsh, because it implies a lack of loyalty in someone who is, for better or worse, a lifelong creature of the Democratic Party.

Then Biden hit back, publishing a post on Medium that included this passage:

But at another level these kinds of attacks are a serious problem. They reflect an angry unyielding viewpoint that has crept into our politics. If someone doesn’t agree with you — it’s not just that you disagree — that person must be a coward or corrupt or a small thinker.
Some call it the “my way or the highway” approach to politics. But it’s worse than that. It’s condescending to the millions of Democrats who have a different view.
It’s representative of an elitism that working and middle class people do not share: “We know best; you know nothing." “If you were only as smart as I am you would agree with me.”

And with that, Biden responded to an arguably unfair criticism from Warren that he was repeating Republican talking points by … repeating a Republican talking point.

There was precisely nothing in Warren’s remarks that suggested she was telling working and middle-class people “you know nothing” and “if you were only as smart as I am you would agree with me.” Where did he get that from?

As Biden knows full well, the “elitism” attack is an old GOP favorite, one the party uses to deflect Democratic criticism of Republicans for doing the bidding of the wealthy and powerful, and to put focus on cultural affinity rather than policy and self-interest. Don’t look at our tax cuts and deregulation, Republicans say, because that Democrat hates you and everything you stand for! He doesn’t love Jesus! He doesn’t hunt! He doesn’t enjoy NASCAR! He’s an elitist who thinks he’s better’n you!

Republicans got so good at this they could throw it out in any context, no matter how ridiculous. George H.W. Bush, product of Andover and Yale, son of a senator, and a guy who used “summer” as a verb, accused his 1988 opponent Michael Dukakis, the son of Greek immigrants and a notorious ascetic who these days literally takes turkey carcasses from strangers after Thanksgiving to make soup out of them, as a product of “Harvard Yard’s boutique.” Bush’s son bought a ranch before the 2000 election to get photographed playing cowboy.

Biden knows all this. But even if his invocation of “elitism” had no evidence behind it, I suspect he genuinely feels that Warren looks down on him. He’s a guy who has spent a career trying to be the representative of working-class people, which until he became vice president included taking the train just about every day between Delaware and Washington, and living modestly.

Biden also engages in a certain amount of mythmaking on this subject, like his regular insistence that “They call me Middle Class Joe — it’s not meant as a compliment in Washington, it means I’m not sophisticated.” In fact, no one in Washington apart from Joe Biden has ever called Joe Biden “Middle Class Joe.” But he says it to beef up an image based in reality.

There’s no question Biden believes that he is the one true voice of the middle class. And this is where it gets complicated.

Warren — who is indeed a Harvard professor after all, albeit one who grew up poor in Oklahoma — has a policy program that is far more aggressively populist than Biden’s. Not only that, she loudly proclaimed that she would do no big-dollar fundraisers with rich people.

By contrast, Biden, like most traditional candidates, is heavily reliant on those events for fundraising and has raised more money from lobbyists than another Democrat. She has been criticizing him about this from the beginning; her campaign once hit him for holding “a swanky private fundraiser for wealthy donors at the home of the guy who runs Comcast’s lobbying shop.”

That criticism may be valid, but Biden thinks of himself as anything but swanky. So what may have him feeling really defensive is the accusation that he — Middle Class Joe! — might be the candidate of the wealthy establishment. Warren may have realized this is a sore point with him; we’ll see how hard she jabs it in the days to come.

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