Jane Fonda: 'Older women have always tended to be the bravest'

On Fridays, Jane Fonda gets arrested.

Police have repeatedly detained the 81-year-old movie star for unlawful demonstration at the U.S. Capitol, where she has joined others in calling for the reduction of fossil fuels. Cameras have captured Fonda in what isn't really a new role for her — outspoken activist — being led away with her hands tied behind her back, sometimes alongside famous friends who have also come to demand action.

"When you're older, what have you got to lose? You're not in the marketplace for some guy who's scared of a strong woman," she told PBS NewsHour anchor and managing editor Judy Woodruff on Thursday. "So you can rise to yourself and become who you are meant to be, and you can be brave."

"Older women have always tended to be the bravest," she added.

READ MORE: Why Jane Fonda is putting herself on the line to fight climate change

Fonda plans to continue these "Fire Drill Fridays" through her 82nd birthday in December. In January she restarts production on her current Netflix TV show, "Grace and Frankie." She said she'll resume participating in the protests next year after a few months of filming.

For Fonda, who famously and controversially protested the Vietnam War, the urgency this time is different: There's an "existential umbrella" hanging over everyone and everything, she told the NewsHour.

What's changed since her Vietnam protest days "is that everyone, not just our soldiers who are in a country fighting the people in that country, but the entire world is being threatened," Fonda said. "This has never happened before in the history of civilization."

Fonda's renewed sense of urgency was partly prompted by the words of 16-year-old activist Greta Thunberg and author Naomi Klein, whose book "On Fire: The (Burning) Case for a Green New Deal" focuses on a climate plan championed by some Democrats.

WATCH: Climate activist Greta Thunberg on the power of a movement

Fonda also felt that she wasn't doing enough. As she told the NewsHour, and describes in videos on her official website, she's made lifestyle changes like driving an electric car, eating less meat, getting rid of single-use plastics. And while those choices are important, it still wasn't enough.

"I had to get out of my comfort zone and put myself on the line, in coordination with the young student climate strikes," such as the Sunrise Movement, she said.

The goal of these Friday protests is not to get the attention of President Donald Trump — the "fossil fuel president," Fonda called him — or his "fossil fuel Cabinet."

"We're trying to get people who are not used to going into the streets and engaging in civil disobedience and risking getting arrests," she said. That has included fellow friends and co-stars Ted Danson, Sam Waterston, and more recently, Rosanna Arquette and Catherine Keener.

"We have to not be afraid," Fonda said. "And we have to see this as the way good citizens of the United States need to act. We need to be in the streets making our demands heard."