1) Aren't the reason(s) that the secular states are refusing to recognize SS marriage due to interference/influence by religious groups or individuals with political influence?
2) Agreed
Probably to the degree that those institutions promote traditional Christian values. Change is in the air though, as more mainstream type gays come out. We see that in the South, where prejudice against blacks lingers far longer than government-backed discrimination. To a degree it's a protective stratagem; if blacks are not racially inferior, then we (our ancestral families at least) did a horrendous thing keeping them in slavery. Ergo, blacks must be racially inferior to prevent us from being descended of monsters. It also gives whites with little going for them someone over whom they can feel superior without having to actually do anything. I think there's a degree of that in homophobia, a desire to both feel superior and to deny having done wrong in the past. There is also the evolution of our government; we are increasingly comfortable on both sides of the aisle with using government to force others to behave as we wish. Or perhaps I have that backward; our government has always been used to enforce a certain uniformity of behavior and we're only expanding its power and reach. Regardless, that only works as long as the discriminated class remains identifiably other. Once one becomes friends or at least acquainted with blacks or with homosexuals and realizes they aren't materially different from the rest of us, such defenses must come crashing down. And to take a Moonbeamish angle, denying that a great evil has been done to one's benefit doesn't make it go away; on the contrary, it binds the evil to us. As long as we maintain that blacks or homosexuals are other and should rightfully bear discrimination for the benefit of ourselves, we willingly embrace that stain on our souls.
I don't totally discount the Christian angle, but it's worth pointing out that such prohibitions are fairly universal, certainly expanding beyond Christianity. It's also worth pointing out that homosexuality is not one of the things on which Christ preached. (I won't presume to guess which sins are important and which are not, but it's always worth noting that modern populations, medicine, and hygiene have rendered moot prohibitions against homosexuality as a matter of population health, much as most of us no longer observe prohibitions against eating pork or shellfish.) I think to the degree that opposition to gay marriage is centered around religion institutions, it's in those institutions's role as the preservers and champions of tradition. And I recognize the value of that tradition, I just don't believe in constraining the freedom of others to keep that tradition. On the contrary, allowing gays into the tradition of marriage will strengthen it, just as accepting that blacks too are created equal and entitled to the same rights as whites enhanced America's other traditions.
All that is to say that I can respect opponents of gay marriage, I simply believe they are wrong. Tradition should not trump freedom and personal liberty, nor should the two even be at odds. Tradition always evolves and as long as the rate of changes are within the society's ability to accept, the evolved tradition should be stronger rather than weaker. And to those with remaining religious rejection, I'd simply ask that you value Jesus' teachings above Paul's or the Old Testament's.