NEW YORK (AP) -- The reputation that Jamie Dimon honed for decades on Wall Street has been severely damaged in a matter of days.
In the 1980s and 1990s, he was the protege of banking industry legend Sanford Weill. In the early 2000s, he took over Bank One, an institution few believed was fixable, and restored it to a profit.
And in 2008 and 2009, at JPMorgan Chase, Dimon built a fortress strong enough to stay profitable during the financial crisis.
His zeal for cost-cutting and perceived mastery of risk did more than keep JPMorgan strong enough to bail out two failing competitors, Bear Stearns and Washington Mutual. It gave him a kind of street cred during the post-crisis years, when he lashed out at regulators who sought to rein in banks, and Occupy Wall Street protesters who raged against them.
Now all that is on the line.
Dimon had to face stock analysts and reporters on Thursday and confess to a "flawed, complex, poorly reviewed, poorly executed and poorly monitored" trading strategy that lost a surprise $2 billion.
The revelation caused traders to shave almost 10 percent off JPMorgan's stock price the following day and brought a shower of complaints from industry observers and lawmakers who said banks needed tighter scrutiny.
Making the black eye worse for Dimon, the loss came in derivatives trading, the complex financial maneuvering that - on a much greater scale - led to large losses and dissolved banks during the financial crisis.
Dimon "staked so much of his reputation on creating this perception of being the ultimate, infallible risk manager," said Simon Johnson, a former chief economist of the International Monetary Fund who is now a professor at MIT. "And along comes this huge mistake."
Dimon, 56, grew up in the Queens borough of New York City, the grandson of a Greek immigrant. His father was a stockbroker who worked for many years at Merrill Lynch.
After college and business school, Dimon turned down an offer from the venerable investment bank Goldman Sachs. Weill had been Dimon's father's boss at a previous job and recruited the younger Dimon to American Express.
Weill became Dimon's mentor. When Weill left American Express in 1986, Dimon followed him to Commercial Credit Co., a sleepy finance firm that catered to middle-class clients.
Weill went on to buy a host of companies, including Smith Barney and Travelers, and Dimon led some of those divisions. The empire-building culminated when Travelers merged with Citicorp to form Citigroup in 1998, the largest U.S. bank at that time.
Dimon was the heir apparent but had started to clash with Weill. Weill was insecure about Dimon's growing assertiveness, and Dimon often showed his temper in meetings. Weill fired Dimon in 1998.
Dimon spent time reading biographies of statesmen and took up boxing lessons to let off steam. In 2000, he became CEO of Bank One, a Chicago bank that was losing money. By 2003, he had turned the bank around, and in 2004 it merged with JPMorgan Chase. Dimon became CEO of JPMorgan in 2006.
By that time, Dimon had lived through several industry crises, including the savings and loan meltdown of the late 1980s, a Russian debt default in 1998 and the dot-com stock bust of the early 2000s.
Dimon was not the man responsible for any of those, of course, as he is for the $2 billion error.
His admission of the mistake this week left some analysts asking whether his grip is slipping, and the bank's more than $2 trillion in assets have become too big for him to manage.
More likely, some other analysts said, it is a statement about how, three and a half years after the crisis, banks still conduct impossibly complex trades that are difficult to track.
"If even Jamie gets it wrong managing a $2 trillion bank, what does it say about banks where management is far inferior?" said Mike Mayo, a bank analyst at the brokerage CLSA and author of the book "Exile on Wall Street."
Just a few weeks ago, while answering questions from stock analysts, Dimon dismissed media reports of big market-moving trades by JPMorgan as a "complete tempest in a teapot."
He admitted Thursday that he should have been paying better attention. Asked to what, he first said trading losses then said, "There was some stuff in the newspaper and a bunch of other stuff."
Dimon's signature trait has been cost-cutting, an attribute that helped the banks he led squirrel cash away. At Bank One, after finding out how many newspaper subscriptions the bank paid for, he is reported to have told an executive: "You're a businessman; pay for your own Wall Street Journal."
That low tolerance for profligacy kept the banks he managed strong enough to weather any crisis. Now, Dimon says the trade that was conducted is so complex that the losses could easily get worse.
JPMorgan's $2 billion loss was caused by trades that were meant to hedge, or protect, the bank from trading losses that could occur in the investments of the bank's corporate treasury.
The amount of the loss was small for an institution of JPMorgan's size - it cleared $19 billion in profit last year - but will hurt its second-quarter earnings and was an embarrassment. It rattled the industry, too. Other bank stocks fell as much as 4 percent Friday.
"It puts egg on our face, and we deserve any criticism we get," Dimon said at a hastily convened conference call with investors to reveal the losses.
During the crisis in 2008, Dimon drew wide praise for keeping his bank healthy, including from President Barack Obama and billionaire investor Warren Buffett. One biographical book that was released soon after the financial crisis was titled "Last Man Standing."
In the years since, other Wall Street bankers and CEOs have cowered as the public backlash against bankers and their bonuses has grown. But Dimon, who made $23 million last year, according to an Associated Press calculation, used his stature to become the most outspoken banking CEO.
He attacked any obstacle that came in his way or his company's - especially regulations aimed at stopping banks from taking the kinds of risks that precipitated the financial crisis. Dimon viewed them as impediments to the bank's ability to make a profit.
He did not even spare the Federal Reserve chairman, Ben Bernanke, or one of his iconic predecessors, Paul Volcker. At times, his outspokenness took on a swagger that raised eyebrows.
At a public forum last year, Dimon pointedly challenged Bernanke to defend his regulatory drive, which he said was going to slow down the U.S. economic recovery.
Earlier this year, Dimon said in a Fox Business Network interview: "Paul Volcker, by his own admission, has said he doesn't understand capital markets. ... He has proven that to me."
One of the most respected Fed chiefs, Volcker has championed a law that restricts banks from trading with their own money.
Since Thursday, Dimon has contended the trades in question were meant to manage the bank's financial risk, not turn a profit, and thus would not be subject to the so-called Volcker rule.
Outside analysts have been more skeptical, and the mistake has breathed energy into the push to toughen financial regulations. Dimon did say that he should have been paying closer attention.
"We know we were sloppy. We know we were stupid. We know there was bad judgment," he told NBC News on Friday in an interview to air Sunday on "Meet the Press."
He said he did not know whether laws had been broken and invited regulators to look into the matter. "But we intend to fix it and learn from it and be a better company when it's done," he added.
Most analysts gave Dimon kudos for coming clean on the trading loss, but few disagreed that his reputation had taken a severe hit.
Said Nancy Bush, longtime bank analyst at NAB research, and contributing editor at SNL Financial: "Jamie certainly cannot be standard-bearer for the banking industry anymore."