Of all the questions posed by the Rachel Noerdlinger saga, the most confounding isn’t, “Why hasn’t the mayor fired her yet?” It’s “Can’t a woman like Noerdlinger do better than this guy?”

A worldly, well-educated professional, Noerdlinger should be positioned to choose a partner far more appropriate than a serial criminal like Hassaun McFarlan. But instead of building a life with an equal, she opted for a man who could destroy the life she’s so carefully built.

It would be easy to blame Noerdlinger — yet this dilemma is faced by all too many of her successful African-American sisters.

Across America, black girls are up to 50 percent more likely than black boys to graduate from high school, report the NAACP and Schott Foundation for Public Education.

In college, African-American women outnumber men by roughly two to one, notes The National Coalition of Black Civic Participation.

And, with black men six times more likely to be incarcerated than white men, educated black women like Noerdinger lack the pool of suitable mates their white counterparts take for granted.

Yet black women show little sign of abandoning the race.

Indeed, of all US demographic groups, African-American women are least likely to date or marry across ethnic lines. Fewer than 10 percent of black women have non-black spouses — less than half the number of black men.

Part of this is external: Troubling 2013 and 2009 reports from dating network OK Cupid revealed that black women are the site’s least-desired demographic — even by black men.

But, as Ralph Richard Banks explored in his 2011 book “Is Marriage for White People?” African-American cultural and community leaders also share the blame for limiting black women’s romantic options.

In his book, Banks, a Stanford Law professor, notes that everyone from the black church to movie director Tyler Perry exhorts black women to partner with black men. So what if she out-earns her mate? Who cares if she’s Ivy-educated while he barely has a GED? No matter if she’s a senior City Hall official and he works as her grey-market “driver.”

For this crowd, finding a black man — any black man — is always preferable to dating outside the race. No matter the cost, Banks bluntly states, black women are expected to “marry down” before they “marry out.”

“Because black men are so beleaguered, black women are made to feel like it’s their duty to ‘help a brother out,’ ” Banks recently said. “Black women face a kind of pressure, a type of survivor’s guilt,” he added, “that simply doesn’t affect white women in the same way.”

These unions can be disastrous — not least thanks to “role reversal”: Intellectually outmatched and economically emasculated, black men get displaced as primary bread-winners while leaving black women burdened and burnt out. Frustrations arise, relationships crumble and the family disintegrates.

Today, 70 percent of all black children are born out of wedlock. And black couples have the highest divorce rates in the nation.

Black women seeking successful family lives, Banks suggests, can no longer afford to exclude other races.

Cut to the wedded security of Noerd­linger’s boss, Chirlane McCray.

As a former lesbian, McCray’s path to matrimony was clearly unconventional. But her choice of a mate — a Caucasian one — helped lead to the happy, successful family that has proven so elusive for Noerdlinger.

“The McCray/de Blasio union makes clear that black women do have options,” Banks observes, “while dispelling the myth that America does not want black women.”

Of course, McCray was a success long before meeting de Blasio, so it would be churlish to suggest she married “out” in order to marry “up.” Rather, her actions better reflect her history as a vocal feminist and intellectual maverick.

After all, when you’ve been gay, resisting black conventions to marry a white man is hardly “radical.” Indeed, with “choice” being the ultimate in female empowerment, marrying de Blasio may actually have been McCray’s most feminist move of all.

Only Noerdlinger can say if she’s “dating down.” What’s clear is that women like her are caught by the painful disjuncture between female and African-American advancement.

These educated, upwardly mobile women have earned the right to choose their own spouses. But tethered to their pasts by baby-daddies and preachers, they may be no more emancipated than their sisters stuck in the ’hood.

The easy answer is for the sisterhood of Noerdlingers to break the chains that hold them back. But perhaps it’s time that men like McFarlan finally begin to set their women free.