With publication of his memoir, The Courage to Act, on Tuesday by W.W. Norton & Co., Bernanke has some thoughts about what went right and what went wrong. For one thing, he says that more corporate executives should have gone to jail for their misdeeds. The Justice Department and other law-enforcement agencies focused on indicting or threatening to indict financial firms, he notes, "but it would have been my preference to have more investigation of individual action, since obviously everything what went wrong or was illegal was done by some individual, not by an abstract firm."

"I think there was a reasonably good chance that, barring stabilization of the financial system, that we could have gone into a 1930s-style depression," he says now in an interview with USA TODAY. "The panic that hit us was enormous — I think the worst in U.S. history."

During the financial meltdown in 2008, the then-chairman of the Federal Reserve would buy a lemonade and head to his seats two rows back from the Washington Nationals dugout, a respite from crisis. But often he would find himself huddling in the quiet of the stadium's first-aid station or an empty stairwell for consultations on his BlackBerry about whatever economic catastrophe was looming.

He also offers a detailed rebuttal to critics who argue the government could and should have done more to rescue Lehman Brothers from bankruptcy in the worst weekend of a tumultuous time. "We were very, very determined not to let it collapse," he says. "But we were out of bullets at that point."



Still, he does acknowledge some missteps by the Fed. Analysts were slow to realize just how serious the economic downturn would become, and he faults himself for not doing more to explain to Americans why it was in their interests to rescue the financial firms that had helped cause it.



"Every time I saw a bumper sticker which said, 'Where's my bailout?' it hurt," he told Capital Download.



That is a rare admission of emotion. Former Treasury Secretary Tim Geithner once described Bernanke as the Buddha of central banking, his demeanor impassive even during disaster. In the 2011 HBO movie Too Big To Fail, actor Paul Giamatti won a Screen Actors Guild award for his portrayal of the Fed chairman as restrained in all things, from his soft-spoken speech to his choice of oatmeal for breakfast. In comparison, Treasury Secretary Hank Paulson seemed almost volcanic.



Not that Bernanke, who retired from the Fed last year, would know about that. He hasn't seen the movie. "I read the book, but I like to say I saw the original, so it wasn't necessary to see the movie," he says.



Will he ever watch it? "If there's nothing else on," he shrugs, "maybe so."

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Bernanke has been interested in the Great Depression since his grandmother told him stories about it from her front porch in Charlotte, N.C., during quiet summer evenings. Her family had been living in Norwich, Conn., where some children went to school in worn-out shoes or even barefoot because their fathers lost their jobs when the shoe factories closed. That meant their families didn't have enough money to buy shoes — which presumably would have kept the factories in business and their fathers employed.

"Even a small boy could see the paradox," he says.



He grew up in tiny Dillon, S.C., a farming town on the Little Pee Dee river. His mother taught school. His father was a pharmacist in the drugstore his grandfather had opened after moving there from New York City in the wake of the stock-market crash of 1929. Bernanke went to Harvard, earned his doctorate at MIT, taught at Stanford and ended up heading the economics department at Princeton.



President George W. Bush named Bernanke to be a governor on the Fed in 2002, then appointed him to head the White House Council of Economic Advisers in 2005. The next year, Bernanke was back at the Fed, succeeding Alan Greenspan as chairman. President Obama appointed him to a second four-year term as chairman in 2010.



Balding and with a neatly trimmed beard, Bernanke has never lost his professorial air and modest mien. He still lives on Capitol Hill with his wife, Anna, who founded the non-profit Chance Academy to help city kids who are being home-schooled. He walks the dog, does crossword puzzles and reads three or four books a week on his Kindle — books of all sorts. In the previous week or so, that included a new annotated edition of Alice in Wonderland; Beyond Words, on the social lives of animals; and the latest Lee Child thriller, Make Me.



His scholarly interest in the forces that caused and prolonged the Great Depression wasn't the reason Bush picked him to come to Washington, but it turned out to be serendipitous.



"When I became chairman, the first thing I did was ask the staff was to dust off the playbooks and see what we had and what the planning was," he said in an interview at the Brookings Institution, the Washington think tank where he is now a distinguished fellow. At the time, few saw a financial calamity on the horizon. "Once we identified what was going on and understood how to take into account (the fact that) we were in a very different financial system than we had been 100 years earlier, that history was very helpful for me in thinking about having to address the panic."

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He wrote the memoir by collecting and reviewing the emails he sent and received during the crisis, perhaps 150 of them a day, a real-time reminder of what was happening. (As chairman, he used a Fed email account but with a pseudonym, Edward Quince, a name that was then listed in the Fed phone book as a member of the security team.)



It reminded him of World War II's North Africa campaign that author Rick Atkinson detailed in An Army at Dawn.



"The main impression you get is how complex and chaotic warfare is, how many things go wrong, how many things fail to work the way you expected them to," he says. "At the end, of course, what counts is ... did the allies succeed in taking North Africa? Looking back on the financial crisis and the period after the crisis, it was a very chaotic period; lots of things went wrong. But I guess in the end we obviously did stabilize the system and the U.S. economy is now growing."



The decision about whether to prosecute individuals wasn't up to him, he says. "The Fed is not a law-enforcement agency," he says. "The Department of Justice and others are responsible for that, and a lot of their efforts have been to indict or threaten to indict financial firms. Now a financial firm is of course a legal fiction; it's not a person. You can't put a financial firm in jail."



He would have favored more individual accountability. "While you want to do everything you can to fix corporations that have bad cultures and encourage bad behavior — and the Fed was very much engaged in doing that — obviously illegal acts ultimately are done by individuals, not by legal fictions."



What the Fed was focused on was trying to prevent the Great Recession from turning into another Great Depression. His academic studies concluded that the Fed's failure to act more decisively and creatively worsened that crisis nine decades ago. This time, he was determined take any steps he could fathom to try to keep a devastating downturn from getting even worse. That approach prompted Time Magazine in 2009 to name him "Person of the Year" and "the most powerful nerd on the planet."

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One early step, in 2008, was to push interest rates nearly down to zero — which is where they have stayed ever since. The current Fed, led by successor Janet Yellen, last month pulled back from indications it was ready to begin raising them again. "We didn't think it would take that long," Bernanke says — that seven years later, interest rates would still be near zero.



Is it time to raise them?



"You know, the last thing I want to do is second-guessing Janet Yellen, who I think is doing a really good job and making some tough calls. But clearly there are some tough decisions to make on how to manage policy at this point, and this is a very important juncture."



Bernanke loves baseball for the same reason he chose economics as his profession: the power and clarity of numbers.

"The numbers are so concrete," he says in a conversation in the Nats press box before a game against the Miami Marlins on a sunny afternoon last month. "In baseball, you've got all the data going back to the 1880s for all the players, and if you understand how to use numbers, it makes it come alive."



He watches the game with the same impassive manner and attention to detail that must have marked his tenure at Fed deliberations. Wearing jeans and a worn blue-gray Nats cap, he doesn't shout and rarely cheers, but he does politely clap when a Nats player gets a hit or the team leaves the field.



"He won't swing," Bernanke predicts as Yunel Escobar faces a 3-2 count. Escobar, who led the league in batting into double plays, has been excoriated in baseball blogs in recent days for doing just that even though star hitter Bryce Harper would have been up next. This time, as predicted, Escobar doesn't swing and gets a walk.



"It's time for Harper to get something," Bernanke says in the next inning as the right-fielder comes up to bat. Done: He hits a home run.

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In 2012, in a favorite moment as Fed chairman, Bernanke was invited to watch the Washington Nationals' batting practice on the field before a game. He was surprised when right-fielder Jayson Werth asked him, "So what's the scoop on quantitative easing?" the Fed's effort to boost the economy by pumping in new money. Bernanke writes, "Then I recalled that Werth was playing under a seven-year, $126 million contract, which gave him some interest in financial matters."



At this game, as Werth heads into the dugout after the top of the first inning, he gives Bernanke a tip of his cap.



Bernanke beams.



Oh, and the Nats won, 5-2.



Ben Bernanke will appear on CNBC's Squawk Box at 8am ET on October 5to discuss his new book "The Courage to Act," the U.S. economy, jobs, China and more.