Former president Donald Trump doesn’t spend much time talking to contentious interviewers. He does a lot of interviews with right-wing media outlets and podcasts with hosts unlikely to press him on the vagueness of his tariffs-and-immigration campaign platform. He knows, as does everyone else, that he simply needs his steady, supportive segment of the electorate to turn out just enough in just enough places to win.

That impulse was very much on display during his conversation with Bloomberg News editor in chief John Micklethwait at the Economic Club of Chicago on Tuesday. The conversation was contentious, with Micklethwait — quite understandably! — pressing Trump on the details of his economic proposals, proposals that are viewed by economists as inflationary and debt-increasing.

But this should be an environment where Trump thrives, right? This is Businessman Trump, the guy from “The Apprentice” (the TV show, not the movie), the one who knows how to make money and pledged to bring that know-how to the whole country. How is it that his conversation with Micklethwait descended into bluster and name-calling, a reversion to his campaign rally habit of doing little but insisting that he would go after a loosely defined group of enemies?

Well, because Trump is Politician Trump, not Businessman Trump — if he was ever the latter at all.

Among other things, Micklethwait pressed the former president on his age. This was an issue that had worked very effectively for Trump’s campaign when he was running against President Joe Biden earlier this year.

“You’ve just said it. You don’t do old,” Micklethwait began. He was referring to Trump’s assertion that, when it comes to Supreme Court justices, “only stupid people put old” people on the bench because “they’re there for two years or three years.”

“You own and run businesses,” Micklethwait continued. “Would you appoint a CEO who was 78, who didn’t give you a medical —”

“Yeah, I would,” Trump jumped in. “Depends on — people like Biden who’s in bad shape? I wouldn’t appoint him. He’s 81 or 82.” Trump went on to say that “some of the smartest people I know” were older.

He used the example of Bernie Marcus, the founder of Home Depot and a political ally of the former president’s.

“He’s just as sharp, mentally — he’s just as sharp as he ever was,” Trump said. “He’s 95.”

But, of course, he’s also not the CEO of Home Depot anymore. That’s Edward Decker, who’s 61.

In fact, an analysis of the CEOs of Fortune 500 companies conducted this year by Madison Trust Company shows that only six of them are older than Trump. Only 1 in 20 is age 70 or older. The average age of those CEOs is just under 60.

The oldest on the list is Warren Buffett, 94 — certainly an exceptional business leader, but also certainly an exception in his longevity.

Another element of Micklethwait’s question is worth picking out, though: the idea that Trump himself is a business success.

The primary company Trump currently owns is the Trump Organization, which is not is not exactly a world-beater in the real estate industry. It owns a lot of property, but revenue from commercial leasing has plunged. Profits at Mar-a-Lago have soared, but that’s in part because of the premium being paid for access to the former president. The most valuable element of Trump’s personal portfolio, according to Forbes, is the parent company for Truth Social, an entity that is understood to be wildly overvalued. His supporters nonetheless buy shares in part as a demonstration of fealty.

Trump’s existence in the world of business is by now almost entirely dependent on his cult of personality. His efforts at generating cash look more like those of a popular celebrity than a business whiz: lots of cheap, often tacky stuff plastered with his name and signifiers of his presidency and political ambitions.

To some extent, this has long been Trump’s approach. “The Apprentice” was a reality show that constructed an alternate reality in which Trump was a business savant, rather than the inheritor of his father’s business and wealth, or someone whose business empire was largely about licensing his last name. This year, one of the show’s producers wrote a lengthy reminiscence about the show, revealing how NBC worked both to plaster over his crumbling real estate empire and to bolster the perception of Trump’s business acumen.

This is why Trump stumbled in his interview with Micklethwait, a venue that should theoretically have been one where he excelled. It’s why he similarly faltered at the Economic Club of New York last month. In 2016, he ran as the businessman who would bring a fresh perspective to politics. Eight years later, he’s running as a proto-authoritarian politician whose perspective on business is “it’ll be fine.” When asked about the economy, he’s running as the guy who was president from January 2017 to March 2020.

The subtext to Micklethwait’s question about Trump’s age was that perhaps it was time for Trump to head out to pasture, that someone his age was a risk as a business leader and therefore as a political leader. When Trump responded that people in their 70s could be perfectly competent leaders, Micklethwait chuckled that it was “strange that you didn’t bring this up when you were running against Joe Biden.”

“No, I never attacked him for his age. In fact, I used to defend him and his age,” Trump replied. “I attacked him for his lack of competence.”

There’s some truth to this. Beyond rendering him “Sleepy Joe,” which is certainly not subtle, Trump — no doubt aware he was holding a rock in a glass house — did often suggest that Biden’s issue wasn’t his age but his capacity. (Trump’s campaign was not as restrained.)

The challenge the candidate faces at the moment is that his competence is starting to draw its own scrutiny. The conversation with Micklethwait didn’t help.