Jane Fonda's back, and I'm worried about her. I'm not quite sure she understands the depth of feeling people have about her. To many she remains a wartime traitor. And even to her admirers she's far from perfect-hectoring, humorless, the archetype of the silly actress who gets in over her head. With all these strong currents flowing about her, it's easy not to see the bigger picture: that she was one of the pivotal figures of recent American history.

She seems an unlikely candidate for the history books. The celebrity books, maybe, but not the important, scholarly tomes written to define the gravitas of the American nation. But there she will be, mark my words, for it was she who defined how Americans should and should not act during wartime. The guidelines she inadvertently set down are followed rigorously to this day, and the emotion they invoke is stronger than ever.

She has an autobiography just out, My Life So Far. I snapped it up. In it she explains her life, and believe me, if there were ever a life that needed explaining it's Jane Fonda's.

First of all, let me say it certainly is interesting. Never before have you read a celebrity bio so full of great material. In one chapter she wins an Oscar. In the next chapter she fights for world peace. In the chapter after that she wins another Oscar-and makes her acceptance speech in sign language.

Each subject she brings up is worthy of a book in itself. Here are just some of them: her mentally ill mother (who committed suicide); her cold, aloof movie star father; her bulimia; her Dexadrine addiction; her career as an actress (everything from Barbarella to Klute); her various activist endeavors; her sex life (she was profoundly affected by The Vagina Monologues and loves to talk about it); her phenomenally successful exercise career; her marriage to one of the richest men in the world, Ted Turner (making love with him was like "a night in Versailles"). Put them all together and you have a story that certainly holds your attention.

And this being Jane Fonda, it's all told in that wonderful voice of hers, on the one hand so totally intimate, on the other so totally self-absorbed. As her theme she has chosen her rocky path through personal growth to an understanding and appreciation of who she is as a person-in other words, ME, ME, ME. And you wouldn't have it any other way.

True, the activism passages do go on. She never met a cause she didn't like, and one tends to lose track. Let's see, there were Bella Abzug and Cesar Chavez and Holly Near and Native Americans and Black Panthers. Now she's into adolescent sexuality and gender issues, which seems perfect-edgy and controversial. But one can't help but wonder-what does she do wrong? What is that false note that keeps appearing? Why don't more people love her for her activism? Is it because something in her make-up, so to speak, makes her see the world as something to complain about, not something to celebrate?

The movie parts of My Life So Far are much better. One tends to forget the breadth of her career; she was the Julia Roberts of her day. There were the great psychological dramas like Klute and They Shoot Horses, Don't They?, the satirical comedies (Nine to Five and Fun with Dick and Jane), the starlet period (Roger Vadim and Barbarella). She's an astute analyst of what makes a movie successful and what makes a character successful, and the description of how she prepared to play Bree Daniels, the call girl in Klute, should be required reading for every ambitious actress.

And then there's Katharine Hepburn. This is the best part of the book. If you're sick of reading those adulatory beatifications about what a great person Katharine Hepburn was, all the time knowing in your heart that it isn't quite adding up, then you've got to check this out. Jane hired Ms. Hepburn to play her mother in On Golden Pond, and, boy, did she turn out to be a handful. Fonda is always respectful, but her portrait of what turns out to be a crafty, conniving and self-obsessed old woman is priceless and probably right on target.

And, finally, there's Vietnam. Fonda's involvement began when she read a magazine article about My Lai, and then, egged on by Simone Signoret, she began to think. The effect was powerful: "Once you connect with the painful truth of something, you then own the pain and must take responsibility for it through action." She soon became a key figure in what was known as the GI movement, which set about to convert soldiers to an anti-war point of view. This was done in off-base coffeehouses. The men were encouraged to confess to doing things that didn't feel right-like killing babies-and the military began to feel very threatened. Not that there were so many soldiers confessing, but those who were got a lot of publicity from Jane Fonda.

Today, I'm glad to say, she has a much clearer idea of how she was coming across. "Instead of reflection all I did was talk-all the time, everywhere, on and on in a frantic voice tinged with the Ivy League ... In interviews I was humorless, talking too fast, in a voice that came from some elitist, out in space place, anger seething just beneath the surface ... Watching some taped interviews years later I wanted to shout, 'Will someone please tell her to shut up?'"

Instead she went to Hanoi all by herself. Once there she met with Vietnamese soldiers, made radio broadcasts, visited hospitals, toured a war crimes exhibit. She also met with American POWs, who swore they weren't being tortured. Then it was off to an anti-aircraft installation on the edge of town.

Jane donned a helmet and listened to a song the Vietnamese soldiers sang. Then she sang a song for them. Apparently it went over pretty well. Giddy and applauding, she allowed herself to be led over to an anti-aircraft gun, where they plopped her down right in the seat and started taking pictures.

Oh, those crafty Vietnamese.

Jane insists the whole thing was an accident, a lapse in thinking, a momentary judgment that will haunt her to her grave, and she's right. But her missteps have a much greater significance than that. She provided the framework, the boundaries of what citizens can and cannot do in wartime. And number one-you don't screw with our troops. You can criticize the President, the Congress, Halliburton, whomever. But you do not mess with the fighting man and woman, even when they're caught red-handed, as at Abu Gharaib. Their pysches are sacred and not to be tampered with. It's a lesson the country has learned so well that these days it goes without saying. An 11th commandment of American life, and we owe it all to Jane Fonda.