Jon Henke at Q&O lays down the libertarian argument for gay marriage and why the state should take a step back from legislating morality:
Immoral does not equal illegal, nor does moral equal legal. Nor *ought* they, and I believe you would agree with that statement.
Consider: would you criminalize gambling, premarital sex, drunkeness or gossip? All of them are immoral in the judeo-christian moral system, yet no libertarian would criminalize them. On the other hand, there’s nothing immoral about driving 45mph in a 35mph zone, crossing a national border at the wrong point or hunting out of season. Yet all are illegal.
Clearly, there’s no inherent connection between legality and morality, nor should there be. (let’s leave aside the more extreme variations of libertarianism)
Go a bit further. Distinguish between the partnership contract sanctified by a Church (marriage) and the partnership contract codified by the State. (marriage) Both have the same name, but they are not the same thing. For clarity, let’s call one “Holy Union” and the other a “Civil Union”. A Holy Union, defined in the Bible and enacted within the Church, carries very different meaning, standards and obligations than does a Civil Union defined in law and enacted by State institutions.
From a libertarian standpoint, the fact that they share the same name is irrelevant. They are still separate and distinguishable.
From a first amendment standpoint, even if one religion (or atheism) allows for two consenting adults to form a union, the state has no business trying to repeal that right with a new amendment. Sexual orientation and partnerships between two adults is free speech that some are hoping to censor and hide.
But don’t let that stop Republicans from . They only seem to do it to rile up their religious conservative base around election time anyways.