NEW YORK – With the global financial community reeling from public outrage and increased regulation, Wall Street is proving incapable of finding a champion to replace the sidelined Jamie Dimon, chief executive officer of JPMorgan Chase & Co.

Dimon, 56, one of the industry’s most forceful advocates, has lost stature as his bank, the largest in the United States by assets, juggles multiple investigations and a $5.8 billion trading loss on wrong-way bets on credit derivatives.

His peers at other big lenders are hobbled by poor performance, tarnished reputations or a reluctance to step into the breach.

Bankers across the Atlantic, including former Barclays PLC CEO Robert Diamond and Peter Sands of Standard Chartered, have been muted by allegations that their firms rigged interest rates or were involved in money laundering.

“What you’re seeing in the financial-services industry is a lack of any kind of credible statesmen,” said Rakesh Khurana, a management professor at Harvard Business School in Boston. Dimon’s diminished ability to defend the industry publicly “basically leaves a vacuum.”

That means the industry is without an advocate to resist the most vigorous onslaught of regulations since Congress separated investment and commercial banking with the Glass-Steagall Act in 1933.

It coincides with the lowest level of consumer confidence in U.S. banks since Gallup began gauging it in 1979. The percentage of Americans saying they had a “great deal” or “quite a lot” of confidence dropped to 21 percent in June from 41 percent in 2007 and more than 60 percent in 1980.

Dimon, whose bank sailed through the financial crisis without a quarterly loss, offered advice and assistance to U.S. presidents, Treasury secretaries and regulators. And he was unapologetic in his criticism of Washington policies and policymakers.

He said former Federal Reserve Chairman Paul Volcker, for whom a new rule curtailing proprietary trading is named, doesn’t understand capital markets. He said bankers will need psychiatrists to evaluate whether trades qualify as hedges. And last year, he took on Fed Chairman Ben Bernanke in a public forum, asking whether anyone has “bothered to study the cumulative effect” of regulation on the U.S. economy.

Now Dimon is “stumbling like an ordinary mortal,” said Thomas Stanton, a former senior staff member for the Financial Crisis Inquiry Commission and author of the new book “Why Some Firms Thrive While Others Fail.” “He’s no longer seen as a purely brilliant manager.”

At least 11 agencies, including the Justice Department and the Securities and Exchange Commission, are investigating JPMorgan for its trading losses.

Last year, the company was one of five mortgage servicers that agreed to spend $25 billion to settle charges they improperly foreclosed on borrowers. The bank also is being probed for possible manipulation of power prices in California and the Midwest.

The JPMorgan loss “strengthens our case,” Rep. Barney Frank, D-Mass., who co-authored the 2010 Dodd-Frank financial-regulatory overhaul, said in May.

“Jamie has become the leading voice calling this unnecessary, saying you don’t know what you’re doing,” Frank said.

The industry has a powerful presence in Washington even without a visible leader. Commercial banks spent $61.4 million lobbying Congress and regulators last year, almost double the $36.1 million in 2006, according to the Center for Responsive Politics, a non-partisan, nonprofit campaign watchdog.

“They’re spending all this money because they know they are in the eye of the storm,” said Bob Biersack, a senior fellow at the Washington group.

Wall Street banks have shifted their allegiance this campaign cycle to Republicans who fought the regulations passed by Congress and signed into law by President Obama.

Four years ago, Goldman Sachs employees gave three-fourths of their campaign donations to Democrats, including Obama. This time, 70 percent of their giving is going to Republicans, according to Center for Responsive Politics data through June 30 compiled by Bloomberg.

Of the 10 companies whose employees gave the most to Romney Victory – a fundraising committee supporting presumptive Republican presidential nominee Mitt Romney – nine were Wall Street firms, according to Federal Election Commission data. Romney, co-founder of private-equity firm Bain Capital, has pledged to repeal new banking rules.

While Dimon played a key role, “there isn’t one singular voice representing the financial sector,” said Rob Nichols, CEO of the Financial Services Forum, a lobbying group in Washington with 20 members, including the six largest U.S. banks.

Still, the lack of a statesman leaves the industry vulnerable, said Greg Donaldson, chairman of Donaldson Capital Management, which oversees $580 million from its headquarters in Evansville, Ind.

“The banks have no moral authority at the moment,” Donaldson said. “Jamie Dimon had it, but that’s done. The government is piling on the banks. They’re just being hammered, and it doesn’t help our economy. Somebody has to fight the damn thing.”