Imagine if a Democratic presidential candidate was asked how they intend to work with Republicans in Congress, and they said this:

“You can’t. It would be malpractice for me or any prospective president to count on getting a single Republican vote on any legislation of consequence. We’re just going to have to work around them.”

It would be a shock, because it would violate the rule which says that Democrats (and only Democrats) must at the very least pay lip service to bipartisanship. But why should they?

This is brought to mind by an interview that Joe Biden gave to CNBC’s John Harwood about his economic plans. Biden, who just released a surprisingly liberal tax plan, has many of the right impulses, but they’re undermined by a bizarre blindness to the history he himself lived through and a complete misunderstanding of how today’s Republican Party operates.

Let’s begin here:

Harwood: But to the point about not your father’s Republican Party, some of the things on your tax and spending agenda are things that Republicans blocked when you were the vice president, before Trump.
Biden: Yes, I agree. But now we’ve had Trump. There’s two ways people get inspired, John. They get inspired by inspirational people like John Kennedy and they get inspired by very bad people, bad presidents like Donald Trump.
And what people have now seen is that his tax policy has been a disaster for the middle-class, disaster for them, and that there is plenty of room to be able to do things that make a lot of sense.

Biden has talked many times about how once Trump is gone, Republicans will shake their heads as if waking from a dream, then become much more reasonable. But here he’s going farther, not just saying they’ll ditch Trumpism, but that they’ll actually support progressive legislation on taxes.

At another point, Biden mentions changes he’d like to make to the tax code, including eliminating the “stepped-up basis” loophole, which allows those who inherit large assets like stock and property to pay very little in taxes. Then comes this:

Harwood: That’s one of the things that you guys tried and couldn’t do under Obama.
Biden: No, but we can now. Once the carny show comes through — with the guy with the pea in the shell, three shells and there’s no pea under any shell — the second time it comes around, they figure it out.

Getting rid of that loophole is an excellent progressive idea. But the reason it didn’t happen under Barack Obama is because elected Republicans have an agenda — cutting taxes for the wealthy and corporations — that they pursue relentlessly even though it’s incredibly unpopular. They do it because they believe in it, not because they think it’s to their political advantage.

So the reason Obama couldn’t get rid of the stepped-up basis loophole was that Republicans in Congress wanted to keep it. If they retain control of the Senate in a Biden presidency, the loophole will remain.

Later in the interview, Biden mentions his proposal to limit the total amount of deductions the wealthy can take. “Another thing Obama tried to do, couldn’t get done,” Harwood says.

“But we’ll get it done,” Biden replies. “Because things have changed.”

But what exactly does he think has changed? Are Republicans in Congress more amenable to progressive tax legislation now than they were five years ago?

Of course not. Biden keeps citing evidence that Republican tax policies haven’t produced the effects they predicted, which is perfectly true, but he insists that now everyone realizes it, so we can finally get Republicans to support a more progressive economic agenda.

The trouble is that the Republican belief in the importance of giving tax cuts to rich people isn’t susceptible to refutation by facts and evidence because it isn’t based on facts and evidence. It comes from a moral judgment they make, that money is a measure of virtue, and therefore the rich — The successful! The job creators! — deserve to pay as little in taxes as possible. That will not change.

Biden seems to think the GOP’s immunity to rational argument just began in 2016. But we’ve been talking about the bogusness of trickle-down economics since the 1980s. Biden was there when Republicans said Reagan’s tax cuts would pay for themselves and bring prosperity to all, and when they said the same thing about George W. Bush’s tax cuts. They were wrong, but they didn’t care.

There’s simply no way Biden doesn’t realize that. Which suggests he sees value in saying that he still might be able to win over some Republicans to his agenda with enough attempts at persuasion and magnanimous good will.

But what is the evidence for that belief? The theory was thoroughly tested in the Obama years, and the results were conclusive. Making a big show of reaching out to the other side doesn’t win you any substantive concessions. If anything it has the opposite effect, since you end up compromising on the front end to show your sincerity, but it wins you no votes in the end.

Being seen as the bigger person doesn’t get you any political benefit, either. Obama’s politeness and efforts to court Republicans didn’t stop them from winning sweeping victories in the 2010 and 2014 midterm elections (though he did win reelection in 2012). Throughout it all, their venomous hatred of him only grew more intense.

Can anyone point to some outcome that was better for Democrats than it would otherwise have been because Obama made a show of reaching out to Republicans?

To be clear, there’s value in reaching out to voters who may have voted for Republicans in the past. Some of them may be receptive to arguments about the failure of Republican economics. But there’s absolutely no reason for Democrats to pretend that Republicans in Congress will ever be receptive to any argument a Democratic president makes.

They certainly aren’t going to abandon policy positions they’ve held for decades just because a Democrat treats them as though they deserve respect. It would be nice to know that the next Democratic president understands that.

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