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Donald Trump and his allies spent a lot of time at the Republican National Convention this week proclaiming that they are on the side of everyday Americans in an ongoing, existential struggle against a wealthy, corporate elite.

It’s the same basic pitch Trump has been making throughout this campaign, and since he first formally got into politics roughly a decade ago. And although it’s a sprawling appeal with a heavy dose of cultural affinity ― yes, that was pro wrestler Hulk Hogan ripping off his shirt on stage Thursday night ― a key component of the Trump campaign is economic. JD Vance, the Ohio senator Trump tapped to be his running mate, made this abundantly clear in a Wednesday acceptance speech that railed against “Wall Street barons” and “America’s ruling class in Washington,” in defense of “the working man.”

This is not the sort of rhetoric you would have heard at previous GOP conventions. And the change has certainly gotten the media’s attention, judging by all the discussion (including in my articles!) about how Trump has injected the Grand Old Party with some good, old-fashioned populism.

It could help him win the election, too, if it resonates with voters who are frustrated with higher prices at the grocery store and gas station ― and who have a sense, going back decades, that neither political party has had their best interests at heart.

One reason Trump can make this pitch so effectively is that he has broken with the GOP establishment on some substantive matters, most conspicuously trade and immigration.

Republican leaders have traditionally tried to keep the flow of both as free as possible, putting them in lockstep with corporate groups and other wealthy interests who feel the same way. Trump is all about building walls that, he promises, will keep out both the foreign goods and the foreign people. And when he’s not invoking racist or nativist tropes as justification, he’s saying the barriers will protect American workers from unfair competition.

But if Trump is the first Republican in recent history to embrace protectionism so completely, he’s hardly the first to say he’s fighting on behalf of non-wealthy Americans. Even Mitt Romney, the plutocrat’s plutocrat and now a senator from Utah, pledged fealty to the working class when he accepted the GOP presidential nomination back in 2012.

And for all of the ways that Trump really is a different sort of Republican, there are a whole bunch of ways that he’s really not.

In fact, if you look closely at the initiatives Trump is promising to roll out and consider the policies he’s pursued in the past, you might come to the conclusion that four more years of his presidency would be a bad deal for the very workers he claims to be defending ― with good reason.

A Closer Look At Trump’s Agenda

Trump wants to slap a 10% levy on all imported goods and a higher, 50% levy on goods from China. He says this will prevent foreign competitors from undercutting U.S. companies, so that the wares available in stores here are made “in America and only in America.”

Tariffs can certainly deter foreign competitors, and nowadays plenty of mainstream economists agree that targeted tariffs make sense as a way to prop up particular sectors, like the auto industry, when it’s in the national interest. But the kind of sweeping, indiscriminate tariffs Trump is eyeing would almost certainly lead to less overall growth and higher prices for consumers. Lower- and middle-income Americans would bear the burden disproportionately, because they tend to spend more of their paychecks on goods rather than services.

But the tariffs are just one part of Trump’s economic agenda. He also wants to cut taxes. He’s floated a few different ideas, including reducing the corporate tax rate to 15% ― a further cut from his 2017 tax law, which moved the top corporate rate from 35% to 21%. Because his campaign does not issue detailed briefings the way his predecessors have, it’s difficult to precisely predict the impact. But the benefits of the 2017 cuts were skewed towards the rich; analysts looking at his more recent rhetoric think his current promises would work out the same way.

One particularly ominous idea is Trump’s suggestion that he could just junk the income tax altogether and rely on tariff revenue to replace it. It’s a fantastical promise that would work only if the federal government took a cleaver to spending or borrowed far more money than it already does.

These possibilities explain why so many economists, representing so many different viewpoints, have trashed Trump’s plans. One analysis from the Peterson Institute of International Economics calculated that his agenda would work out to $1,700 in higher annual costs for the typical family, which is pretty much the opposite of what he’s promised people reeling from the price of food, gas or housing.

Trump’s agenda, the report’s authors concluded, would “entail sharply regressive tax policy changes, shifting tax burdens away from the well-off and toward lower-income members of society while harming US workers and industries.”

A Closer Look At Trump’s Record

Economists can be wrong, of course, and distrust for academic experts is as much a part of Trumpism as contempt for corporate elites. But that’s what’s so strange ― and ultimately so telling ― about Trump’s agenda. Instead of repelling wealthy leaders of the business community, Trump has been winning them over.

After a meeting with roughly 100 CEOs from a variety of industries in June, several emerged saying they’d decided to support Trump with contributions. And that’s on top of the backing he’s hotten from a handful of tech titans ― including Elon Musk, who recently pledged $45 million a month to a Trump-aligned super PAC.

Trump reportedly courted the CEOs with promises of tax cuts and fewer regulations, and he touted a proposal about tipping that illustrates the true nature of his populism almost perfectly.

The proposal would exempt tips from the income tax. That sounds great for waiters and other service workers ― a good proxy for the working class, though they represent just 5% of the low- and middle-income workforce. But, as Howard Gleckman of the Tax Policy Center noted recently, most “make so little income that they already pay little or no income tax.”

Oh, and the proposal could be a boon for hedge fund managers and other members of the country club crowd, depending on proposal details, because of opportunities it’d create to game the tax system.

As is always the case with Trump, it’s difficult to know how seriously to take any vows he makes, whether behind closed doors in a C-Suite or on a convention stage in front of a national television audience. But this is where Trump’s record comes into play, and not just his record on tax cuts.

Trump rolled back workplace safety rules, gutted protections against wage theft and filled federal agencies with anti-union officials, as Dave Jamieson detailed here at HuffPost last year. And, of course, Trump tried to repeal the Affordable Care Act, a.k.a. Obamacare, which would have taken health insurance away from millions.

That record may not be a perfect guide to how Trump would govern in another term. But it’s probably a more reliable indicator than the show he put on in Milwaukee this week, or anything else he says between now and Election Day. And so while it’s clear Trump has refashioned the Republican Party, it’s less clear his changes are the ones working Americans had in mind.