Do not get me wrong: this is not an attack on Mr. Eubanks, or his opinion, per se. It is the fallacious manner in which is presented; how a lot of these anti-gay arguments are presented. Here are a few things wrong with arguments based on slippery slopes.
All too often, they are based on a false dilemma. In other words, there is no logical reason to juxtapose polygamy with gay marriage, especially when you are talking about two forms of marriage. A rose by any other name, is still a rose, and gay marriage is still the principle definition of marriage, a union between two consenting adults. Polygamy, clearly, is not that. An article published by Slate.Com illustrates the problems with polygamous, or polygynous, unions and why they can present more problems not only for society, but for the individuals involved in this practice.
An argument based on holy doctrine is irrelevant in a secular society. This is America - and in America, we are guided by the Constitution of the United States of America, not anyone's particular religious book. Mr. Eubanks cited examples of Abraham, Moses, Jacob and Solomon, characters unique to Jewish, Christian, and Muslim teachings. But these are examples that should not and cannot play any role in forming laws governing the right to marry, or how many individuals can in fact marry. What one or multiple groups finds morally reprehensible has no bearing on the right to practice or to live by which those individuals oppose. To enact laws based on religious beliefs would be unconstitutional, our First Amendment clearly states.
It is dishonestly marketed as religious persecution. I have personally had to deal with argument from fundamentalists in which I was called a bigot and intolerant for not respecting the rights of the religious to discriminate based on their religious beliefs. The normal par-for-the-course response is "Why can't I profess my faith without being called a bigot or homophobic?" This is what I have to say about this: You have every right under the law to believe as you see fit and to speak your piece (with consequences and with provisions - see the last line of the preceding paragraph), but those beliefs are not immune from scrutiny, and they are not automatically warranted a free pass because you hold them dear. The religious beliefs of someone are not threatened or usurped because a gay/lesbian couple is able to marry or because the majority of societal opinion on gay marriage has shifted in favor.
The argument is clearly meant to be anti-gay. On the surface it may appear to be a reasonable question, but you read the op-ed presented by Mr. Eubanks, it becomes clear that maybe his argument is less about being in favor of polygamy, and more about being opposed to gay marriage, which there is nothing wrong with. We are all free to believe and think as we wish. But a little amount of intellectual honesty would be greatly appreciated, especially when making broad based claims with little more to go on than personal feelings.
It would also behoove those who try to use the comparison of gay marriage to polygamy to remember one key thing: gay marriage bans specifically target gay and lesbian couples and is a direct violation of the Fourteenth Amendment's Equal Protection Clause. Polygamy bans extend to everyone. In other words, if you're straight, gay, lesbian, bisexual, transgender, religious, not religious, black, white, it doesn't matter; you cannot enter into a legally binding polygamous union. This ban does not discriminate against anyone because it is equally distributed across the board. Mainline Mormonism (Church of Jesus Christ of Latter-day Saints) in America had to drop polygamy as an acceptable practice in order to join the United States as the state of Utah.
In conclusion, I would just like to say that I do not believe that those who believe that marriage should only be between a man and a woman are bigoted. However, if you put those beliefs into actions, you most definitely are, and there is no way around that. Just because I am for gay marriage does not mean that by the same extent I would have to support polygamy, and that not doing so would make me a hypocrite. They have nothing to do with each other, and if your only argument is a moral and religious one, there is nothing more to say.