So, finally, thanks to a vacation, I got around to reading — well parsing — the bestselling phenomenon du jour: Fifty Shades of Grey by E. L. James, the romance novel that deals in S&M sex between the ludicrously named would-be dominator Christian Grey and his “oh-I-don’t-want-to-be-submissive-or-do-I?” partner Anastasia Steele.

Why did I put myself through this? To be clear: it was not for sex — or literary — education. No, my straight hairdresser tells me he’s reading it to improve relations with his female clients who have all read it — surreptitiously, on their Nooks. So, I feel it’s my job, as an author, corporate publicist, TV commentator to understand modern culture, probably every bit as much as my hairdresser, who assured me: “There’s not much in it you wouldn’t find in a Harlequin romance.”

Well, yes and no.

I haven’t read a Harlequin romance since I was about sixteen but I don’t think you’d find whipping, spanking, and hitting in a “red room of pain” in a regular romance read.

But Fifty Shades of Grey is not really about S&M sex at all. Its appeal is that it’s a brilliant psychological thriller — albeit a truly horribly written one.

The book keeps you turning the pages because you want to know how far he will push her, mentally, physically; quite regularly he tries to control her food intake, which appalled me until I realized that I’ve watched husbands on New York’s Upper East Side admonish their emaciated wives, in public, not to have dessert, so perhaps this isn’t as weird as I originally thought — but far more importantly, why does he do this?

You sense he both does and doesn’t want to do this to her — and this is one of the book’s two great strengths. He is hugely conflicted by his mysteriously self-imposed role as the dominator. He does and doesn’t want to hurt her.

That’s why the title suggests he is complicated: it is called Fifty Shades of Grey… not Blue and Orange: A Story of Why Two People Were Completely Wrong for One Another… So how will his inner conflict play out, as slowly he falls in love with her?

And as for her? This is the book’s second strength: and the bigger one. Her story is really about her psychological development as a woman on a complicated, intense journey from virginity to learning what it is she really wants from men, from relationships — but far more interestingly, what does she want for herself? This, I think, is the book’s ultimate appeal. The real reason why it’s on top of the New York Times Bestseller list, leaving more established authors — and publishers — scratching their heads.

The book’s great seduction is that is poses a question most women — and for that matter, men — grapple with, secretly, usually every day. They don’t express it because it’s not very politically correct. Would you choose a life of security over love? The answer is supposed to be “of course not.”

Anastasia initially falls not just for Christian Grey’s sex appeal, but for his billions, his helicopter, his glider, his cars, his clothes, his brains, his wit, his vulnerability, and, yes, his controlling tendencies, the fact he’s a challenge; she realizes he’s in love with her — or the closest he’s ever come to being in love — and even so part of him is untouchable. So once she’s fully hooked by him, the question remains what should she do about their emotional (as opposed to sexual) inequality?

In this book she leaves…

But how many women would have the courage to leave like Anastasia when they could have all that money, power, sex — but not love on equal terms?

Think again of those New York women being told not to have dessert by their husbands in case they gain weight; think of the husbands who brag: “My wife is seven months pregnant — and look — she’s only gained ten lbs.” (Yes, I’ve heard this more often than I care to remember.) I think of the tortured look in so many women’s eyes — most of them mothers and wives — as they struggle to be seen for who they really are. Anastasia realizes she is caught in an unequal emotional relationship. Unlike most people who have those sorts of trappings on offer, she chooses for herself: she runs.

So, Fifty Shades of Grey, with all its ghastly prose, raises serious and important questions for women — and, actually, for men. And, nope, I didn’t think I’d be saying that about a so-called “mommy porn” book.