Jamie Dimon Is Competing With Everyone. He’s Not Alone

When Jamie Dimon turned to competitive threats in his shareholder letter this year, the chief executive officer of JPMorgan Chase & Co. did something unusual: He named some. Citadel Securities LLC and Revolut Ltd. were two of the firms Dimon picked out. He could also have added Apollo Global Management Inc. and even Pacific Investment Management Co.

Right now, financial firms from different disciplines are veering into each others’ lanes more freely than at any time since the 1990s. This blurring of business lines is going to accelerate with the White House push for deregulation in banking and markets. Technology, too, keeps making it easier and cheaper to strike out into new fields. For clients, that could be great news. Competition can drive down costs, make markets more efficient and benefit anyone who needs to borrow or trade. But history shows there can also be major downsides. Too much finance can be a dangerous thing when it leads to poor credit judgement, excess lending and weak risk management.