(FORTUNE Magazine) - In 1996, after he had been retired from the auto industry for three years, Lee Iacocca told FORTUNE that he had "flunked retirement." Today, at 81, Iacocca is as restless as ever. "I've gotten better at retirement, but it has taken a long time." He spoke with FORTUNE senior editor Alex Taylor III about his life, his business ventures, and his latest cause: saving the country.

You sound as if you haven't lost any of your energy. What's your secret for a fulfilling retirement?

At 65, you are going to say, "Will I be financially okay?" You worry about the IRS and estate taxes. But we're living so much longer, what are you going to do with your life? If you don't stay engaged, it hurts you physiologically. A couple of my bosses at Ford (Charts) retired at 65, and they went home to die. They were dead by the time they were 68. They had no interests. When you atrophy, you die. Retirement isn't the end; it is the beginning.

How do you stay busy?

I'm spending more time with my family: seven grandchildren--four girls, three boys. That's the good time. I keep up with some guys at Chrysler (Charts) - a lot of them are gone. But I don't subscribe to Automotive News anymore. That's too much.

I'm in the midst of a book for Simon & Schuster called Where Have All the Leaders Gone? But they didn't give me $8.5 million like they gave Greenspan.

How do you feel?

My health is good. I walk two miles a day and go to the gym. I was smoking one cigar a day, but I was having bronchial trouble, so I gave them up for 3½ months, and I didn't miss them.

I've got the house in Bel Air and it has a tennis court, but I don't play much because I have a hard time finding partners. I should probably play with [billionaire and Iacocca friend Kirk] Kerkorian. He's 89 and plays every day. Everybody asks me why he bought General Motors (Charts) [Kerkorian owns 9.9% of the company], and I say, "Hell if I know." But he's a gambler - he likes the game - and he did make a couple of billion dollars' profit from Chrysler. I've got a friend - Vic Damone, the singer. He's retired too. He plays golf twice a day, and he enjoys it. But I don't play golf anymore. I've sold most of my car collection, but I still have Viper No. 1 and the last Town and Country convertible ever built. I had an MG TF restored when my first granddaughter was born so that I could give it to her when she was 16. It's 51 years old, and it looks so good I won't let her drive it. I was going to build a house and put it in the library and rope it off.

You still do a lot of work for your diabetes foundation. [Iacocca's first wife, Mary, died from the disease in 1983.]

That's one where I'd like to get a cure before I die. It is not a huge foundation, but it is up to $55 million. [Iacocca himself has contributed $35 million.] I hope that is my legacy. We're getting so damn close to a cure; it may happen in my lifetime, but I have to be careful about what I say. You don't want to give false hope to people who have it.

When I did those four commercials for Chrysler last year, they gave me five million bucks, which I donated to the foundation. I spent 24 hours with Snoop Dogg and didn't understand a word he said to me the whole time.

Have you found anybody to share your life with?

I have a good friend and companion. I met her ten years ago. She was my trainer and masseuse. She's a good girl, and she takes care of me. I also have a housekeeper and a driver. I like to drive, but out here [in California] I get lost once I get off the freeways.

What's happened to your business ventures?

I picked some of the wrong stuff through friends. Koo-Koo-Roo [a chicken-restaurant chain] sounded great. We could have sold it to McDonald's (Charts), but I didn't want to spend my time in the chicken business. Electric bicycles were taking so much time - they were taking more time than I spent running Chrysler. GM was my partner on my neighborhood electric car. I spent five or six or seven million dollars of GM's money, and I decided the country wasn't ready for a full electric car.

I don't give speeches anymore. I got off the circuit. I used to enjoy that. You could go anywhere in the world - take one or two people with you - they'd pick up all the expenses and pay me 75 grand for 30 minutes. Flying isn't too bad if you can skip the airports. I had a company plane for 50 years. For short trips I lease a plane, but that's too expensive for flying across the country. People figure I've flown over 10,000 hours, and I'm sort of tired of it.

How's the new book going?

I'm excited about it. My first book - my autobiography - was easy. I probably dictated 40 hours to tape. I've done about 15 hours of tape so far on this one. Writing this book is a tough son of a bitch. I'm getting into all these other topics--immigration, globalization, the global village, how GM and Ford lost their way.

Why am I writing a book at all? I'm a patriot. I think this country is screwed up royally, and I can't sit idly by while it goes to hell. We have to stand up and lead before we're taken over by the Chinese. Out of the past nine Presidents, I probably voted for five Republicans and four Democrats. A pox on both their houses. I could have run for President in 1988 as a Democrat-Independent, but I'm glad I didn't.

When I was at Chrysler, I only took a salary of $1 a year, though I made a lot of money on stock options. When I saw Lee Raymond of Exxon Mobil made $400 million in one year--that's pretty absurd. How do you explain that?

I don't have to pull any punches [in the book]. You have to be more decorous when you are running a company, but I'm not worried about that anymore. I never in my lifetime saw so many people who are so affluent, but they are all anxious. Is anybody happy anymore?

I've had a good life. Why am I still pissed off? I'm not the last angry man. I'm just disappointed we're not making any progress in the world.