It's February in Miami.

Blue skies, a balmy day.

And inside a luxury hotel on South Beach, the ballroom is packed with Wall Street types.

It's an escape from the wintry weather in the northeast, which is where most of these guys are based.

And, you know, they come out, they bring their polos and their swimsuits.

They're here for a working vacation.

If your idea of a vacation is J.P. Morgan's Leveraged Finance Conference.

And they come to talk about how to make a lot of money

and then have a lot of cocktails,

court some business, toast the deals of last year.

Our colleague Alexander Saidi was there, taking it all in,

including the conference's main event,

a keynote addressed by the High Priest of American Banking.

Well, the star of the show is none other than the celebrity CEO himself, Jamie Diamond.

Jamie Diamond is the CEO of J.P. Morgan Chase, the biggest bank in America.

Diamond is a legend in the banking world.

Partly because of how successfully he steered J.P. Morgan through the 2008 financial crisis.

He's known for his level head, his discipline, and his caution.

And in the midst of this sunny finance party, he was about to be a buzzkill.

Jamie Diamond said he was worried about a trend he was seeing in financial markets, in something

called private credit.

It's a type of lending to companies that's largely unregulated, growing like gangbusters,

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