Today Hillary Clinton’s campaign is going to roll out its first attack on Donald Trump over the economy, with an early afternoon speech in Ohio; a new web video attacking Trump’s statements on economic policy; and a new website, Art of the Steal, dedicated to attacking Trump’s career as in business.

The key line: "He’s Mitt Romney but bad at his job."

Clinton’s two arguments about Trump’s businesses

The line encapsulates the twofold argument the Clinton campaign wants to make about Trump as a businessman.

On the one hand, they want to say that he’s been ruthless and profited off decisions that were costly to middle-class people. That’s an argument Barack Obama’s campaign pressed against Romney in 2012, and it’s one that Democratic Party operatives believe was highly effective.

My read of the evidence is that arguments focused on Bain Capital actually didn’t do much to help Obama (Romney outperformed GOP Senate candidates in essentially every state, for example). But I rarely talk to anyone who works in Democratic politics who agrees with me, so it’s no surprise they’re trying it again. The way Trump made millions in Atlantic City while running failing casinos that ended up stiffing contractors, bondholders, shareholders, and workers features prominently here.

On the other hand, they want to say that at least Mitt Romney was genuinely good at getting rich. Trump, by contrast, was born rich, and they say his actual investment record is unimpressive. Since 1987, for example, he’s underperformed an index fund investment.

The vexed question of Donald Trump’s wealth

Normally inquiries into a politician’s personal finances don’t tell you much about his likely performance in office.

But there is nearly no precedent (Wendell Willkie is the exception) for a major-party nominee who has no record of service in public office, so there isn’t really much to go on with Trump except his business career. This is especially true because Trump isn’t exactly running what you would call a wonky, detail-oriented, policy-heavy campaign.

And the truth is that we honestly don’t know that much about Trump’s business career. In Atlantic City he was operating in a highly regulated industry and briefly ran a publicly traded company, so we have disclosures around some of that stuff. But the vast majority of the pies Trump has had his fingers in over the years are privately held companies, and we have no real idea how well they have performed over the years.

If Trump released his tax returns, it would be pretty easy to tell what’s going on. The one journalist who has seen the returns can’t talk about their contents, but he does say Trump isn’t nearly as rich as he says he is. The fact that Trump doesn’t actually appear to be able to self-finance a presidential campaign strongly implies that he’s not the multibillionaire investor he says he is. But the truth is we don’t know.

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