Every moralist, gay or straight, concedes that our passions – even the most deep-seated and undeniable urges—remain notoriously unreliable guides to happiness, productive relationships, and even long-term health. By supplanting the old imperative to “do your duty” with the new commandment “follow your heart,” the Love Generation embraced emotion as the standard for judging all intimate arrangements and explorations.

This new emphasis produced its most damaging impact not through the indulgence of new sexual alternatives, but with the exploding rate of divorce in the 1970’s. If marriage rested on feeling rather than obligation, it naturally proved more evanescent and disposable. Before the sexual revolution, many families might quietly hum the Righteous lyrics “We’ve Lost That Lovin’ Feeling,” but relatively few of them actually broke up their relationships. Commitment, tradition, honor and duty all helped to keep most couples together, even through difficult times.

Gay marriage serves to move matrimony even further toward the primacy of feeling. The chief argument for treating gay attraction as equally deserving of respect and support as man-woman-love is the depth, sincerity and undeniable nature of the passion that same sex partners feel for one another. The language promoting such couplings always emphasizes emotion rather than duty or commitment or tradition; same sex partners can hardly take their position in a long, sacred line of succession back to the beginnings of time. Yes, every society has included gay people but no civilization ever sanctioned gay marriages. Redefining matrimony as “an expression of love” rather than a public and profoundly consequential social contract damages the understanding of the institution for all elements of society.

3. Treating Male and Female as Interchangeable . Before John Gray and other astronomers of the intimate discovered the vast distance between Venus and Mars, before “Gender Feminists” revealed the natural superiority of women, before even Hollywood reconnected with the joys of girly-girls and manly men, the “Equity Feminists” of the ‘60’s and ‘70’s preached the interchangeable/indistinguishable nature of males and females. According to some psychological theorists of the prior generation, “gender” amounts to a socio-cultural construct, an artificial distinction meant to subjugate women. Enlightened pre-schools encouraged girls to play with trucks and forced boys to nurture dolls, confident in the expectation that kids of all genders would grow up equally adept as nurses and police officers, nuclear physicists and homemakers. Equality between men and women, according to the thinking of the time, meant the minimization of their intrinsic differences, and the erasure of the time-honored concept that each individual required a partner of the opposite gender for ultimate completion. The popular Ms. Magazine slogan, “A woman needs a man like a fish needs a bicycle” expressed the prevailing derision for the belief that both genders brought something distinctive, precious and irreplaceable to a relationship.

The promotion of gay marriage requires the same dismissal of gender differences: if a woman and a man bring utterly distinctive attributes to any marriage then same-sex unions lack the balance, the fusion-of-opposites energy, that constitute the very essence of male-female partnership. If men and women possess fundamental, unavoidable contrasts involving their physical, intellectual, emotional and spiritual realities, then it’s ridiculous to claim that a male-male partnership is the same as a female-female partnership – let alone comparable to the combination of manly and feminine elements that characterize traditional marriage.

In a sense, the position of gay rights advocates has become contradictory. If replacing a bride with a second groom on the wedding cake makes no difference in the nature of the marriage, then a female partner is interchangeable with a male partner. And if the core differences between men and women count for so little, then it’s hard for homosexuals to claim that they can only feel attraction to their own gender. If men and women are, essentially, the same, then why can’t gay people choose opposite sex partners and spare us all the trouble of redefining the nature of marriage and upending the social order?

Despite politically correct protestations to the contrary, men and women remain, and will always remain, vastly and incurably different and for most homosexuals choosing a convenient opposite sex partner seems as unthinkable and unacceptable as my choosing another male. Science can’t fully explain the origins of homosexual impulses, but it’s a terrible mistake for defenders of traditional matrimony to describe it as a “lifestyle choice.” Most people – gay and straight alike – never choose their orientations, and every American deserves respect and liberty and privacy.

Insisting on equal rights for individuals, however, hardly requires the equal treatment of all relationships. The demand to recognize same sex unions as virtually identical to male-female marriage isn’t just a matter of extending an ancient, honorable institution to new customers. It is, rather, an unprecedented effort to redefine and restructure that institution at its very core and, in the process to breathe new life into three dysfunctional old ideas definitively discredited many years ago.