In Ernest Hemingway's "The Sun Also Rises," someone asks Mike Campbell, the troubled Scottish war veteran who is engaged to Lady Brett Ashley, how he ended up bankrupt. "Two ways," Campbell replies. "Gradually, and then suddenly." Campbell's interlocutor goes on to ask what brought about his collapse. "Friends," Campbell says. "I had a lot of friends. False friends. Then I had creditors, too. Probably had more creditors than anybody in England."

It's too early to determine whether Donald Trump might be headed for the same fate as the wretched Campbell, but there are intriguing parallels. Not so long ago, Trump also had lots of friends and creditors. Many of these friends held powerful positions in the worlds of business and politics. His most important creditor was Deutsche Bank, which, during the past decade, had defied internal dissension and extended hundreds of millions of dollars of loans to him. On top of these invaluable relationships, Trump had nearly ninety million Twitter followers, a vast audience that appeared to provide lucrative possibilities for monetization after he left office.

But, in the week since Trump incited a mob of his supporters to attack the Capitol, he and his businesses have suffered a series of blows. Key corporate partners have abandoned him; some of his fellow-billionaires have spoken out against his sedition; Deutsche Bank has let it be known that it doesn't want anything more to do with him; and Twitter stripped him of his following. When Trump leaves the White House, next week, he may have his eyes on planning a return to the political stage, but surely his first priority will be stabilizing his business empire--if he can manage it.

If the corporate shunning of Trump persists and expands to other businesses owned by him, it could do immense damage. Trump's hotels and resorts, such as the Trump National Doral, in Miami, depend on big businesses to fill their ballrooms and function spaces. They also rely on wealthy individuals to book the tee times, hotel rooms, and weddings that provide daily revenues. His condo developments cater to wealthy buyers. Other Trump ventures, particularly his licensing deals around the world, are even more dependent on the enduring appeal of the Trump brand, which is now in question.