One of the most intriguing questions in respect of President Trump is why he was the only businessman to throw himself heart-and-soul into the race for the presidency. Americans, after all, are a people who celebrate capitalism. So why did the other billionaires fail to make a similar effort, throwing themselves hook, line, and personal jetliner into the race to lead America out of the Great Recession?

We ask because of the remarks this week of the chairman of J.P. Morgan Chase, Jamie Dimon. He has fetched up at the top of the Drudge Report with a boast, made at his bank’s headquarters, that he could defeat Mr. Trump in a presidential contest. “Because I’m as tough as he is. I’m smarter than he is. I would be fine. He could punch me all he wants. It wouldn’t work with me. I’d fight right back.”

Good for him, we thought — until Mr. Dimon backtracked faster than a lobster at a clambake. “I should not have said it,” he confessed. “I’m not running for president.” The outburst “proves I wouldn’t make a good politician,” Mr. Dimon demurred. “I get frustrated because I want all sides to come together to help solve big problems,” he explained, according to the account at CNBC.

CNBC, it turns out, has a whole list of billionaires, chief executives, and celebrities whom it reckons Mr. Trump has inspired to run for president. The list includes, among others, Howard Schultz of Starbucks, Bob Iger of Disney, investor Mark Cuban, Mark Zuckerberg of Facebook, as well as Kanye West and Oprah Winfrey. What stands out, though, is the uncertainty of their trumpets.

Our own favorite of this ilk is Mayor Bloomberg, who served three terms in New York. To win his first term as mayor he spent almost a sixth as much as Mr. Trump would later spend winning the whole presidency. We’re a kiloparsec or two to Hizzoner’s right. Yet we’ve probably issued more editorials urging him to run for president than any other publication.

When we pointed that out to him (at a book party in Manhattan in early 2016), the ex-mayor cheerfully said he’d do it on one condition — that we do away with the electoral college. We told him we’d get right on it. If we’d made good on the jest, maybe he would have run. Instead, Mr. Bloomberg went to Philadelphia and gave a speech at the Democratic convention attacking the only billionaire to actually run.

Go figure. The thing about Donald Trump is that he wasn’t scared of the electoral college — or, it seems, the 16 other contenders in the Republican primary of 2016. Nor was he scared of the popular vote. Or the Democratic Party-dominated press. Also, too, unlike his Democratic opponent, the real estate magnate eschewed a popular vote strategy and pursued the electoral college head on.

Some will speculate that Mr. Trump was just smarter than the other billionaires, perceiving a path to victory where they couldn’t. Or more courageous. Or simply loved his country more than the others did. Or was more confident in his own ideas in respect of the political economy. We’re not partial to one line of speculation over the other. We’re just remarking that he was the only billionaire to step up.

Which brings us back to Mr. Dimon. At one point he is quoted by CNBC as saying about running for president, “Anyway my wife wouldn’t let me.” What a contrast to Mr. Trump. With all the newspapers that got it wrong and all the billionaires who shrank from the fray, the only advice his wife, Melania, is on record as having given to him is to bear in mind that if ran he would win.