Sharon Krum talks to child star and trailblazing radical feminist Robin Morgan

Anyone expecting Robin Morgan to fit the outdated stereotype so often applied to radical feminists (humourless, screaming, scary) would surely want their money back. Now 65, the woman who began life as a child star, before sending a lightning bolt through 1970s America with her anthology, Sisterhood is Powerful, is, in person and in print, both thoughtful and searingly intelligent. Entering her ground-floor Greenwich Village apartment, where a framed letter from Simone de Beauvoir hangs near the entrance, she walks me out to her garden: her pride and joy. "The garden keeps me sane," she laughs.

Which is lucky, because, after six years of the Bush administration, with its attacks on legalised abortion, the pushing of creationism in schools and the launch of a disastrous war in Iraq, Morgan has felt ready to explode. What particularly rankles is the way the Bible has been used to justify it all. (President Bush once said that God had asked him to run for president.)

And so, this month, her response to what she calls the American Taliban - her book, Fighting Words, a Tool Kit for Combating the Religious Right - hits US and online bookshops. In it she unpicks the myth propagated by rightwing politicians that America was founded as a Christian nation.

"The Constitution does not refer to a deity, on purpose," she notes. "The founders, who were educated Englishmen and radicals, believed strongly in the separation of church and state.

"Madison, though devout, thought there shouldn't be chaplains in Congress. Washington stated the US government was not in any sense founded on the Christian religion. And Jefferson made it clear that the presidency was about civil power only."

What has been the most egregious sin (as Bush might put it) committed by this administration? "I think what has happened to poor women is the worst," she says, "because of the cutbacks on abortion. People who say, 'Oh, my god, we might lose Roe v Wade [the 1973 supreme court decision that legalised abortion],' just don't seem to get it. We have already lost it when 84% of all counties in the US lack an abortion provider."

"What is devastating is the cynical mobilisation by the ultra right of people of faith for political power, and in this case to bring about dominionism, which is the plan to take over government and make it a Christian nation.

"And it always starts with possession of, and restriction of women, because if you can control women you can control reproduction and the family, which is the bedrock of society."

When I tell Morgan her personal trajectory would make a great movie, the former editor-in-chief of Ms. magazine gives a knowing smile.

"Bizarre, yes?" she says. At the age of four she landed her own eponymous radio show, Little Robin Morgan, before starring in the popular TV series Mama from the ages 7-14. "I did enjoy parts of performing as a child, even if it wasn't my idea," says Morgan, who became an actress thanks to a "stage" aunt and her mother.

"But in my teens and early 20s I didn't want people to know about it. I worried it made me seem special, like some crazy elite New Yorker, and I wanted to reach the woman in curlers at her ironing board in Kansas."

Of course, the media couldn't help themselves, and Morgan famously walked off The Tonight Show in 1969 when it screened vintage footage of her as she spoke about the first national march against rape. "Imagine talking about such a subject and having it trivialised like that."

After her childhood stint in television she pursued her love of words. She studied at Columbia University and worked as an editor while becoming involved with the new left, which, she says, led her to feminism.

"We [women] were tired of making coffee and not policy. We were shocked when we articulated this and found our revolutionary brothers threw tomatoes and rocks at us, so we split off."

Morgan went on to become a founding member of New York Radical Women and was involved in campaigns such as the protest of the Miss America contest in 1968. At the same time she was married to poet Kenneth Pitchford (who was gay), and they had a young son. After her divorce, Morgan had a long-term relationship with a woman, and today she is single. The thought of another intense relationship "tires me out," she jokes.

In 1989 she presciently published The Demon Lover: The Roots of Terrorism, in which she argued that terrorism has a strong sexual component, and that, as a culture, we eroticise violence.

Why have women begun signing up for suicide missions? "If you're a smart young woman with guts, living in the Gaza strip,' says Morgan, "what are you going to do to make yourself visible and respected? And the men who recruit them are almost always lovers, so there is still an erotic component to it."

I ask her about today's feminist movement and refreshingly she is "impressed by their energy and passion".

And her greatest pride is the rise of grassroots global feminism. "It's unstoppable . . . and continually gives me hope that that's where feminism will heal the world."

And whether those rolling up their sleeves call themselves feminists, well, frankly, she doesn't care. "I often hear women don't want to call themselves feminists, and if [someone] has trouble with the word, OK - she can call herself a squirrel as far as I'm concerned. As long as she keeps on fighting for herself, and for other women." Just as Morgan, herself, always has.