If President Biden sometimes sounded a lot like Donald Trump during his State of the Union address, boasting about a record of economic nationalism, the imitation may soon run the other way. Biden’s attacks on congressional Republicans for being allegedly eager to cut Medicare and Social Security were a clear preview of how he hopes to run against the G.O.P. in 2024. But they were also a possible preview of how Trump may try to reclaim his own party’s nomination — by reprising his 2016 campaign’s rejection of Tea Party austerity and attacking potential rivals (which means, primarily, Ron DeSantis) as libertarian dogmatists who don’t care about the middle class.

That strategy was previewed a bit recently by Joseph Zeballos-Roig and Shelby Talcott in Semafor. Their subject was the so-called Fair Tax, a longstanding fascination for certain right-wing activists that proposes to replace the U.S. tax code with a sales tax. This would yield certain advantages in economic efficiency; it would also result in a dramatic tax increase on the middle class.

In the heyday of the Tea Party, when implausible policy proposals were all the rage, the Fair Tax was endorsed by many of today’s 2024 hopefuls: by Nikki Haley, Mike Pence and Mike Pompeo and, yes, by DeSantis himself. Which gives Trump a license to accuse all these potential rivals of supporting a middle-class tax hike — and the Semafor writers quote a Trumpworld source basically promising an attack along those lines, to force Trump’s rivals to “answer for what they supported and what they’ve advocated in the past.”

That same quote could easily apply to the proposed entitlement changes that many Republicans (again, including DeSantis) embraced in the same era, under the influence of Paul Ryan’s budget blueprints. Those proposals were serious rather than crankish, if ill-timed for a moment when there was more fiscal space than deficit hawks believed. But they were also seriously unpopular, and Trump’s discarding of them was crucial to his success in 2016. And having discarded them then, he’s well positioned to go after DeSantis and others now — in imitation of not only his prior campaign but also, as National Review’s Philip Klein points out, the strategy pursued by Mitt Romney in the 2012 primaries, when he sank Rick Perry’s candidacy in part by blasting Perry for calling Social Security a “Ponzi scheme.”

This means that the non-Trump G.O.P. can expect to spend the looming presidential race facing similar attacks from the Biden White House and the Trump campaign. Making the similarity too obvious could backfire on Trump. But the peril for the G.O.P. is that even if Trump can’t beat DeSantis by harping on his past positions, he will still be reinforcing for swing voters the liberal narrative that (non-Trump) Republicans care only about the rich.

In one sense that narrative shouldn’t be too hard for DeSantis to counteract, since his record as governor of Florida is more moderate than libertarian — with increases in teacher pay, support for environmental protection and so on — and it’s not clear that voters care that much about long-ago votes if they aren’t tied to specific policy proposals now.

But the question is what exactly DeSantis’s more of-the-moment policy proposals would be, in a fiscal landscape constrained by inflation for the first time in decades. There’s certainly a scenario in which he abjures austerity and embraces pro-family and industrial-policy spending, maybe even finds a few modest tax increases that own the professional-class liberals, and thereby evades the Trump-Biden pincer.

But it won’t be easy to pull off. Especially because part of Trump’s strength has always been that he doesn’t need the Republican Party’s donor class in the way that normal politicians do, while DeSantis will need to rally that class if he’s going to dethrone the former president. And the price of their support will be, most likely, something that isn’t particularly popular: not an idea from the fringes like Fair Tax or a big entitlement overhaul proposal, necessarily, but at the very least a budget-eating tax cut that probably won’t be populist in any way.

Again, 2012 is an interesting precedent. Part of what killed Romney in that general election was that even though he championed Social Security against Perry and declined to embrace any crankish tax proposals, he still ended up saddled with a tax overhaul plan that donors and activists liked but that was easy for the Democrats to attack.

It’s not hard to imagine a DeSantis candidacy that rallies the establishment and defeats Trump only to end up in a similar general‌-‌election position. Which suggests one way in which Trump’s populist attacks on other Republicans could actually be helpful to the party’s chances. They’ll leave no doubt, for DeSantis or any other figure, about the political weaknesses of traditional right-wing policymaking. And they might force an early adaptation that otherwise could come, like Romney’s attempted pivots in 2012, as too little and too late.

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