When 17-year-old Jan Rose Kasmir raised a chrysanthemum to the tip of a soldier’s bayonet during a march on the Pentagon protesting the Vietnam War, Marc Riboud captured the moment in what became one of the most iconic photographs of that era.
Today, Kasmir marched once more in Washington, D.C. for the first time since the picture was taken in 1967.
Kasmir tells TIME it was the right moment to march again because she’s been shocked and frightened of how the country has tolerated and elected a leader “who has no dignity, who has no integrity,” she says. “I see things happening that absolutely amaze and disgust me. I think right now we’re in some kind of, I don’t know, psychotic episode of American history. It’s just so outrageous.”
Now 50 years after she marched on the Pentagon, the self-described hippie and peace pilgrim joined protesters in the capital for the Women’s March on Washington.
She’s come a long way since she marched as a teenager. The famous flower power photo of Kasmir shows what she later described as “overwhelming sadness” over realizing the members of the National Guard, blocking the protestors from reaching the Pentagon, were just young boys being told what to do.
The photo landed in newspapers across the world and has been a mainstay in history textbooks and photographic retrospectives ever since.
But Kasmir says she didn’t know the picture even existed until at least 20 years later, she says, when her father picked up a book of Magnum photographs at an airport. She wrote a letter to Riboud to identify herself, and interest in her started trickling in.
Learning about the photo’s popularity showed her that her actions could make a difference. So after she finishes a book she’s working on, Kasmir says she plans on traveling to schools and college campuses to tell young people it’s never too early to make a difference. “I think that everybody right now is in a state of shock,” she says. “We have to do something with this energy. What’s important is we can’t just let it fizzle out.”
Peter van Agtmael is a photographer and member of Magnum Photos.
Julia Zorthian is a reporter at TIME. Follow her on Twitter.