When Malala Yousafzai, the 16-year-old schoolgirl and youngest Nobel nominee, appeared on the Daily Show this month, host Jon Stewart seemed, for the first time, disarmed.
Later, he'd be left speechless by her eloquence but his first, stuttering words to her were: "It's honestly humbling to meet you. You are 16 ..." Those two statements sum up an internationally felt, two-part awe: first, how is she so brave and formidable and, second, how is she so young?
Malala has been a campaigner for girls' rights to education since she was 11, when she began blogging for the BBC about life in Pakistan under Taliban rule, but she became an international symbol of peaceful resistance and valour after an attempt on her life last year.
She has said that up until then, despite being told that she was a target, she couldn't believe that anyone would try to shoot a teenage girl. Instead: "I was worried about my father [also an activist] - we thought that the Taliban are not that much cruel that they would kill a child."
Her courage and her achievements are enormous regardless of her youth: She has defied arguably the world's most tyrannical and brutal regime, and she not only survived an assassination attempt at 15 but was emboldened by it. In a speech delivered at the United Nations soon afterwards, she said: "The terrorists thought that they would change our aims and stop our ambitions but nothing changed in my life except this: Weakness, fear and hopelessness died. Strength, power and courage was born."
All this is more than enough to justify the worldwide adulation she has elicited. But what makes her compelling even beyond this, and why she will endure, is the fact of her girlness.
Like her, we all find the idea of someone shooting a child in the head unconscionable. But when that child is a girl, it seems more shocking: We are told that girls are vulnerable, more vulnerable than boys. More insidiously, we are told that girls are trivial, dismissible and inherently risible. The word "girl" remains something like an insult - to throw like a girl, to act like a girl.
US Secretary of State Hillary Clinton seemed to acknowledge this girl-scorn and to celebrate its subversion when she joined the ranks of world leaders praising Malala. Speaking in April, she said: "The Taliban recognised this young girl, 14 at the time, as a serious threat. And you know what? They were right. She was a threat."
Malala, then, is not just an emblem for peace: she's heralding a shift in the way we valourise and lionise girlhood.
Lorde, aka 16-year-old New Zealander Ella Yelich O'Connor, has not survived gunshot wounds to the head or been nominated for the Nobel peace prize, but she is, like Malala, now a near-global teenage heroine. (One who's just released a debut album aptly, if impudently, named Pure Heroine.)
There isn't anything novel or remarkable about a teenager topping the charts - youth has always been pop's favourite commodity - but there is everything novel about a school-age pop star who speaks eloquently about feminism, cites writers such as Wells Tower and Tobias Wolff as influences, and references the relationship between Raymond Carver and Gordon Lish.
Lorde's poise and precocity are at play in Royals, which has been the number one song in the US for the past three weeks. This has to be the first time that a critique of wealth - sly and knowing and lyrical and written by a schoolgirl - has found itself a number one hit.
Lorde has a fan, and vice versa, in 17-year-old Tavi Gevinson, who began her career at 11 with Style Rookie, a fashion blog so astute that national news outlets suggested it was written by an insider.
In the years since then, Gevinson has deftly navigated her way from fashion world curio to a global media powerhouse, a 17-year-old public figure idolised by as many adults as teens.
Rookie, founded in 2011, announces itself as a site for teenage girls, but with some of the most enlightened interviews and columns around it has found as passionate an audience among grown women. I'm nearly 30, but, like every woman I know, I read her website every day.
Of the many astute things to come out of Gevinson's mouth, this might be the most important: "Feminism to me means fighting. It's a very nuanced, complex thing, but at the very core of it I'm a feminist because I don't think being a girl limits me in any way."
Figures such as Tavi, Malala and Lorde - girls publicly admired for their convictions and the boldness of their actions - might help us all reclaim "girlhood" as a state of strength. Through them, we might start to think of the term "teen idol" differently. We might, in fact, upend it entirely. Because rather than pubescent celebrities adored by tweens (and monetised by the music and movie industries) for their non-threatening attractiveness, these are teenagers idolised by adults for their intelligence and courage.
Pop culture loves the kick-ass version of girlhood. It's a lineage that began in the girl-power 1990s with Buffy the Vampire Slayer and runs on to Xena: Warrior Princess and Katniss of The Hunger Games. But, to put it bluntly, these girl characters are presented as heroes simply through the violence they enact. They look cool doing it, but to borrow Malala's words: "You must not treat others with cruelty and that much harshly; you must fight others through peace and through dialogue and education."
Ilana Nash is an associate professor at Western Michigan University in the gender and women's studies department and the author of American Sweethearts: Teenage Girls in Twentieth-Century Popular Culture. I ask her why it is that the culture is yielding these real life girl-heroes now.
"Teenage girlhood has followed a parallel motion to the women's movement of the 1960s and 1970s. Just as it was a result of second-wave feminism for women to become political icons, so is it now possible for teenage girls to be admired and publicised as political agents. In other words, girlhood is starting, in a small way, to follow the same trajectory that adult womanhood has in the last generation."
In a recent interview with Kamila Shamsie, Malala reflected on the Talib who shot her: "He was quite young, in his 20s ... he was quite young, we may call him a boy."
We might - and allowing him his youth is an act of almost superhuman magnanimity on her part. When she calls him a boy, she's virtually pardoning him. In contrast, when we now call her a girl we're simply paying her a compliment.