Trump watchers have been treated to a world-class cage match over the last couple of days between President Donald Trump and one of his political Svengalis, Steve Bannon.

Lots of attention has been lavished on Bannon's charge, leveled in a new book by the journalist Michael Wolff, that Trump's son, Donald Jr., engaged in "treasonous" behavior by meeting with a Russian lawyer in Trump Tower during the 2016 presidential campaign. There are also requisite antics involving others in the Trump clan and the White House.

All of that is entertaining, as is Trump's furious counterattack. He posits that Bannon has "lost his mind" and on Wednesday night unleashed one of his lawyers to warn his former chief strategist that if he kept yapping about life with the Trumps he'd get taken to court and suffer other miseries. (Wolff apparently has recordings of his Bannon interviews and Trump granted Wolff access to the White House, so legal remedies for the president may be elusive.)

But one of the more substantive issues Bannon has surfaced shouldn't get lost in the cacophony. Bannon, in his interviews with Wolff, has invited us to consider the families of Trump and his son-in-law, Jared Kushner, as possible targets of a significant federal money-laundering investigation.

Bannon is dismissive of the Trumps and how haphazard and reckless they were during the campaign — in part, no doubt, because they didn't think they'd win. That lens allows Bannon to understand exactly why the Trump campaign has drawn the attention of the Justice Department's special counsel, Robert Mueller, who is investigating possible links to the Kremlin, and who has already indicted Michael Flynn, Trump's former national security adviser, and Paul Manafort, Trump's former campaign manager, on an array of criminal charges.

Bannon also knows, as any street-fighter would, that Mueller's probe is perilous for the president because it is much more than an investigation into Russia's election meddling on Trump's behalf — and Bannon zeroes in candidly and coolly on that fact.

"This is all about money laundering," Wolff quotes Bannon saying. "Their path to [expletive] Trump goes right through Paul Manafort, Don Jr. and Jared Kushner." For good measure he added, "It's as plain as a hair on your face."

"It goes through Deutsche Bank and all the Kushner stuff," Bannon adds. "The Kushner stuff is greasy. They're going to go right through that." (He used a nastier word than "stuff," but let's keep things family-friendly around here.)

Bannon then roasts the Trump White House for how ill-prepared it is to take on Mueller's team: "They're sitting on a beach trying to stop a Category 5."

The Trump family has had longstanding real estate and licensing dealings with questionable business associates, some of them Russian and some of them not, as I and reporters like the late Wayne Barrett have written about for years. The family's recent departure from its ill-fated Trump SoHo hotel project, and its partnership with career criminals like Felix Sater, are reminders of how problematic some of those deals will be in the context of Mueller's investigation.

Trump allies have recently targeted Mueller's probe as ill-founded, tainted with prosecutorial bias, and the work of a conspiracy orchestrated with Democratic partisans and the "deep state." But the reality is that Mueller, a well-regarded, veteran prosecutor, has been running an investigation by the books.

It's an investigation that is likely to continue examining matters beyond political collusion, which Mueller's original mandate allows for, and will continue to involve explorations of financial dealings by the Trump family and members of the Trump campaign (particularly those involving Russia).

Bannon knows this, and his comments to Wolff show that he knows how devastating all of it could be to Trump and his children.

The speed and intemperance of Trump's counterpunches suggest that the president probably feels himself at risk, too. There were many reasons Trump may have had for lashing out, of course. Bannon painted him as someone surrounded by ignorant, scheming relatives, lacking any interest in governing, pursuing the presidency as a marketing lark, and an empty vessel that others could fill with their own ideas — in other words, exactly the guy who's been occupying the Oval Office for the last year.

Bannon's (and Wolff's) stuff was so compelling on Wednesday that it drowned out much of the chatter Trump sparked the night before when he tweeted that his nuclear arsenal was "bigger & more powerful" than North Korea's.

It never takes long for the president to lash back when someone makes the mistake of criticizing him, belittling the first family or usurping the spotlight. Bannon hit the trifecta and did all three.

"Now that he is on his own, Steve is learning that winning isn't as easy as I make it look," Trump advised in a statement the White House released on Wednesday. "Steve was rarely in a one-on-one meeting with me and only pretends to have had influence to fool a few people with no access and no clue, whom he helped write phony books."

Little of those latter observations ring true. Bannon may be a crackpot, but he certainly had the president's ear during the campaign's home stretch and in the early, shambolic months of the Trump administration last year. And as Bloomberg News' Joshua Green detailed long before others caught on, Bannon is a media-savvy operative who understands in his own peculiar way what makes some people tick. So Trump won't find it easy to dismiss what Bannon has said with a few broadsides.

Bannon knows that Donald Jr. and Kushner are potential liabilities for the president, especially in the context of a sophisticated money-laundering probe. And he also knows how ill-equipped the White House is to contend with the legal hurdles and financial inquiries that lie ahead of it. He knows all of this, even if he has lost his mind. That's why the president wants to shut him up and shut him down.

Timothy O'Brien is the executive editor of Bloomberg Gadfly and Bloomberg View. Twitter: @TimOBrien

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