The picture of Phuc, taken by an Associated Press photographer on June 8, 1972, is famous in every corner of the world, but few know her name or whether she even survived.
An overflow crowd recently gathered at the Lobero Theatre in Santa Barbara hoping for a chance to hear the now 49-year-old woman speak.
Phuc has matured with grace and charm. She is a goodwill ambassador who is now comfortable telling her story.
Upon meeting her, I noticed she is always at ease, smiling and remarkably open. Our conversation started with the memory of that painful day 40 years ago in her small village of Trang Bang.
"I saw four bombs and I heard sounds, 'Boom, boom, boom, boom,' and suddenly fire everywhere around me and then the fire burnt off my clothes," Phuc said.
She said the pain is still a daily part of life. It never goes away. Her left arm, entire back and neck are all disfigured. There's horrible scarring to her skin, but even more so to her self esteem.
"Every time I touch it, I scare myself to death," she said. "That's why I thought I'd never have a boyfriend, get married or even have a baby - normal life."
As she candidly revealed, that world-famous photo only added to her misery.
"First time when I saw that, I wish that picture not taken because that little girl, I feel ugly and embarrassed," Phuc said.
She credits her faith in helping her heal and find happiness. Today, she is married and a mother of two.
"Now, as an adult, as a mom - I'm a mom - I learned that I'm so thankful that he took that picture," Phuc said.
She said she's thankful because the picture gave her purpose. She now travels the world, speaking on behalf of innocent victims of war.
"Being in her presence is like being with a monk, someone who has gone to the depths of her spiritual journey," said Alethea Parady, who runs Friendship Tours World Travel, a unique opportunity for high school students to visit historically important locations. "She exudes a humanity that one would think is scarcely possible considering the suffering she has endured."
I traveled with her students from Santa Barbara to Trang Bang, where the photo of Phuc was taken. Visiting Trang Bang gives young Southern Californians a much deeper understanding of what Phuc and her family had to live through in the war.
"Kids are naturally compassionate," Parady said. "When they see that photograph, they recognize themselves because she is a universal image of children."
In nearby Ho Chi Minh city, they visited a war museum where Phuc's photograph hangs along with many other images of the war. As they stared at Phuc's picture, its importance was much clearer.
"I have seen this picture countless times before we came on this trip, but the first time I saw it today I stared at it for 10 minutes because it was like a whole new picture after hearing Kim's story," said 16-year-old student Mica Zimmerman. "I had a whole new perspective of it. It's like a completely different picture."
The picture won the Pulitzer Prize for photographer Nick Ut.
Phuc is a gateway to understanding what war is, and providing that clarity to people around the world helps her chase her own pain away.
"I have rich spiritually, I have peace, I have joy. Like you see, I smile all the time," she said with a laugh.
In 1992 while on a honeymoon with her husband, they courageously defected while their plane was refueling in Canada. They have lived in Toronto ever since and she has devoted her life to helping children.