This resistance of the religious right to gay marriage is unfortunate
since far from weakening traditional family values it would actually
strengthen them by extending those narrow moral guidelines to an entirely
new group of individuals -- homosexuals.  

Currently the gay community accepts and even encourages a wide variety of
sexual lifestyles from simply living together to polygamy to open
relationships to promiscuous sex lives to gay marriage.  Of course, gay
men and lesbians do marry today even without civil acknowledgment but no
homosexual couple would argue that their marriage is somehow superior to
any of the other types of relationships that the gay community engages in.
Knowing that their gay marriage is as frowned upon as any other type of
gay relationship places all gay sexual choices on equal ground.

However, granting public acceptance to gay marriage changes everything.
Public acceptance of gay marriage will make it seem superior to all other
gay sexual mores.  The difference will be subtle and unconscious at first.
If two women choose to simply live together other homosexuals will wonder
why they don't marry now that the option is available.  If a man continues
to be sexually promiscuous it will be considered simply a phase until he
finds someone he wants to marry and settle down with.  Those attitudes
don't seem overtly judgmental, but in fact they assume that such sexual
behavior is somehow inferior and that the goal for everyone should be the
superior state of matrimony.  That is precisely the attitude that
heterosexuals take toward marriage.  (The current trend toward straight
couples living together might seem to indicate otherwise, but I would
point out that living together is always considered a prerequisite to, not
a substitute for, marriage.)  

Marriage also carries with it certain tacit understandings, specifically
fidelity, romance and sex taboos.  It's commonly accepted that a man who
cheats on his wife (or a woman who cheats on her husband) is a poor
spouse.  Theoretically an open marriage should be judged by different
criteria.  Strictly speaking a person is not cheating since the spouse is
aware of what is going on and is, in fact, doing the same thing.  It's
rare, but some heterosexuals do participate in open marriages, however,
they seldom talk about them.  It certainly isn't the sort of thing
heterosexuals discuss casually around the dinner table.  Why not?  Because
among heterosexuals it is simply assumed that if a couple needs to find
sexual intimacy from someone other than their lawfully wedded spouse then
there is something wrong with the relationship.  An open marriage is a
failed marriage.  

That same guideline of fidelity would be applied to homosexual marriages
as well.  Already most gay men and lesbians who hold wedding ceremonies do
so with the assumption that their relationship will be monogamous.  If gay
marriage is legalized then those gay couples who do have an open
relationship even after marrying simply won't talk about it for fear of
disapproval from both their heterosexual and homosexual friends.

One problem with discussing open relationships is that thanks to the sex
taboos it is considered impolite to discuss sex publicly at all.  There
are certainly heterosexual couples who participate in S/M sex play, role
playing or use pornography and sex toys in their love-making but, when
such things are discussed at all, it is usually discussed in hushed tones
to close friends and certainly not declared out loud to the general
public.  Marriage itself creates the sex taboos by assuming that sex will
be done privately in one's bedroom.  Making private intimacies public
knowledge is considered bad form.  

Gay men, on the other hand, will casually discuss their relationships
around a dinner table.  (I can't say if this is also true of lesbians.)
Gay men also make no secret of their interest in S/M, porn or sex toys and
will discuss such topics with just about anyone short of their mother (and
sometimes even with their mother.)   When they think about such things at
all (and they don't often) gay men and lesbians assume that marriage will
not significantly affect their sex talk but it will, simply because
heterosexuals don't want to hear it. Heterosexuals have a romantic notion
of sex as requiring only two souls and two bodies and, whatever else they
may be, porn and sex toys are certainly not romantic.  

For that matter sex itself, with its sweating and moaning, isn't
particularly romantic either which is another reason they don't like to
talk about it.  Heterosexuals want to maintain their romantic notions of
sex and marriage at all costs so it's best not to examine them too
closely.  Acceptance of gay marriage would be assumed to include a tacit
agreement to preserve the romance and thus be contingent on gays and
lesbians abiding by fidelity guidelines and sex taboos since it is
"impossible" to have one without the other.  

Which brings me back to my assertion that gay marriage will not destroy
traditional family values but will even more firmly entrench such morality
by applying heterosexual notions of monogamy, fidelity, romance and sexual
taboos to homosexual relationships as well.  Open relationships,
promiscuity, S/M, porn, sex toys, drag and other sexual mores outside the
straight norm will go back into the closet that the gay community has
struggled so hard to get out of.