Watching my 3-year-old daughter twirl around the room in her aqua tutu and gold plastic tiara, I marveled at how she had come to this point all on her own. After all, I was raised by feminist hippies.

Believe me, I’m more than aware of the arguments against princesses. Part of me has even wondered if daring to write a pro-princess book was asking for trouble (sensing my agenda, would my daughter become a preschool Goth just to spite me?).

“Heart magic. Princess power. Feminine ferocity. It’s all the same. And our world does not need less of it — it needs more.”

So as a mother, I’ve treaded carefully; always avoided the pink aisle and never actively pushed any kind of princess play. And yet here she was — reigning over me in all of her splendor and enjoying every bit of it.

I have to admit that I love my daughter’s princess persona. Without a doubt it involves an element of glamour (my Kate Spade jewelry is often pilfered to accessorize her flammable princess gowns), but it also involves an element of pure power. She may be playing princess, but in doing so, she is truly a queen-in-the-making. And it’s a joy to watch.

Our alpha-female battles began when she was just 6 months old. She is what many politely term a “strong-willed” child. In the words of William Shakespeare, “She is but little, but she is fierce.”

And yet, when she wears her tiara and wields her wand, our mother-daughter conflicts subside. Her confidence in her own omniscient royal power allows her to become softer towards me, kinder towards everyone and more enchanted with everything around her.

For little girls, princesses represent a world of female empowerment that’s hard to find anywhere else. And when it comes to the princess genre, what’s the real sexist problem? The fact that princesses are marketed to girls? Or the fact that society demeans everything that girls like?

Princesses are easy targets because our society automatically dismisses anything feminine as weak or second best. I’m not saying we should remove all critical thinking when watching Disney movies or reading old fairy tales, but my real problem with princess-detractors is the attack on girliness itself.

In “Defense of the Princess,” I stand up for fairy-tale princesses of all kinds, but also for the princess in everyone — the princess inside you can be the female body you were born with, the female gender you identify with, or the feminine way you choose to express yourself. Whatever way you want to talk about it, “girly” does not mean inferior. And everything masculine is not the default ideal.

Feminist author Naomi Wolf once said, “Don’t worry if your 5-year-old insists on a pink frilly princess dress. It doesn’t mean she wants to subside into froth; it just means, sensibly enough for her, that she wants to take over the world.”

And we need girls to start taking over the world! As Madeleine Albright pointed out, “Women’s empowerment is not merely a goal, but a cornerstone of democratic growth. Women raise issues that others overlook, devote energy to projects that others ignore, and reach out to constituencies that others neglect.”

With that in mind, I am incensed by the notion that the male way automatically equals the right way. And fingers crossed, our daughters will grow up to become equally incensed. In the meantime, princess play offers them a blissful window to feminine power that exists nowhere else.

Many girls “outgrow” the princess phase because society tells them it’s silly, that “girly” girls aren’t sensible girls, that femininity and power are polar opposites. I’m hoping that at least a few will refuse to listen.

It’s OK to be frustrated with the excessiveness of princess-themed marketing, but we mustn’t call for all princess paraphernalia to be thrown on a bonfire. Because by rejecting everything princess, we send a dangerous message: that being a girl is not good enough; that feminine expression is a source of shame.

If you look closely, princesses have always been about power, not passivity; they are women who are born to rule. And we are short-changing our daughters if we allow them to think anything else.

“Mummy?” my daughter asked me recently (growing up in London, she has a very cute British accent). “When is my magic going to come out? It’s taking a long time.”

“I’m not sure I know what you mean.”

She became slightly exasperated, “The magic in my heart! When is it going to come out of my wand?”

Heart magic. Princess power. Feminine ferocity. It’s all the same. And our world does not need less of it — it needs more.

Jerramy Fine is the author of “In Defense of the Princess: How Plastic Tiaras and Fairytale Dreams can Inspire Smart, Strong Women” (Running Press), out this week.