It's almost as if somebody told the country's most influential bankers that they had better stir up some good will in the heartland.

Vikram Pandit, chief executive of Citigroup, was in St. Louis two weeks ago to talk with Washington University students, and John Stumpf, chief executive of Wells Fargo, gave a speech Friday at St. Louis University. Both took time for press interviews, and both defended their giant banks against charges that they're too big, too powerful and too dependent on government aid.

"The business model we have is meat and potatoes," Stumpf said. "It starts with customers. We don't have big trading businesses. We look it as the same thing we did back when, just with more zeroes and in more places."

Citigroup, with $1.9 trillion in assets, is the third-largest U.S. bank. Wells Fargo, at $1.2 trillion, is No. 4. They're widely considered to be among about a dozen

financial institutions that are too big to fail, because the collapse of an enormous bank might cause credit to freeze up throughout the world.

A growing body of thought, however, holds that if a bank is too big to fail, it is too big to exist. If bankers know they can reap profits during good times, and tap taxpayers for bailouts when things go wrong, they're likely to take more risks than they should.

"It's just an intolerable situation, and it's no way to run an economy," said James Bullard, president of the St. Louis Federal Reserve Bank, who was also on the speaking circuit this week.

Politicians have proposed various remedies for the too-big-to-fail problem, from breaking up the giant banks to hitting them with special taxes or higher capital requirements.

Stumpf doesn't think those solutions are workable. "I have a hard time understanding how, within reason, more capital can cure problems caused by poor management or a poor business model," he said. He also pointed out that Wells Fargo is only the 20th-largest bank in the world, implying that size limits would hurt U.S. banks' ability to serve their customers.

Pandit, who has shrunk Citigroup by about 25 percent, said the problem at his institution wasn't size but strategic clarity. After spinning off the Travelers insurance business and reducing the amount of risky trading that Citigroup does, Pandit said the bank has narrowed its focus.

"We are the world's global bank," he said. "Not a supermarket, not a financial services company, we're a bank."

Hmm. That sounds a lot like the plain-vanilla message that Stumpf came to deliver. These bankers may have been speaking in St. Louis, but their intended audience clearly includes 535 men and women on Capitol Hill. Congress is considering various proposals for regulatory reform, and it's sure to address the systemic-risk issue in some way.

Pandit pointed out that Citigroup is the only one of the top four banks that has shrunk since getting government assistance through the Troubled Asset Relief Program, or TARP. Stumpf argued that "we have done what we've been asked to do" with the bailout money. "We've lent out more money than any other recipient," he added.

Both banks, clearly, were chastened by the events of the past year. Both CEOs may indeed be turning their banks into model institutions that take fewer risks and focus on customers' needs.

We will have future crises, though. Until we can say for certain that banks like Citigroup and Wells Fargo are not too big to fail, we haven't really learned our lesson from the last one.