For years, defenders of natural marriage have been derided for claiming that redefining marriage to include same-sex partnerships would logically open the door to polygamy. And when Bill Kristol and others drew attention to this point in Chief Justice Roberts’ Obergefell dissent, where he argued that limiting marriage to two parties is merely arbitrary in the majority’s reasoning, liberals laughed.

Rolling Stone went so far as to cite the point as one of “the nastiest gay marriage dissent quotes”:

The language is cold, snide and postures outrage … they rail against unelected judges, insist marriage is rooted in procreation and warn that America is now on a slippery slope to polygamy.

But the thing about slippery slopes is that sometimes you slide down them. Case in point: same-sex marriage proponent Fredrik deBoer has come out with a piece in Politico arguing for polygamy based on the fact that the same-sex marriage ruling logically opens the door to it:

The question presents itself: Where does the next advance come? The answer is going to make nearly everyone uncomfortable: Now that we’ve defined that love and devotion and family isn’t driven by gender alone, why should it be limited to just two individuals? The most natural advance next for marriage lies in legalized polygamy…

DeBoer also cites Roberts’ dissent, but rather than accusing Roberts of slippery slope alarmism, he wonders why polygamy is such a bad thing. “As is often the case with critics of polygamy,” deBoer writes,  Roberts “neglects to mention why this is a fate to be feared. Polygamy today stands as a taboo just as strong as same-sex marriage was several decades ago.”

DeBoer openly applies the logic of the argument for same-sex marriage to the argument for polygamy, and is up front about what he sees as the hypocrisy of those SSM proponents who oppose polygamy:

Progressives who reject the case for legal polygamy often don’t really appear to have their hearts in it. They seem uncomfortable voicing their objections, clearly unused to being in the position of rejecting the appeals of those who would codify non-traditional relationships in law. They are, without exception, accepting of the right of consenting adults to engage in whatever sexual and romantic relationships they choose, but oppose the formal, legal recognition of those relationships. They’re trapped, I suspect, in prior opposition that they voiced from a standpoint of political pragmatism in order to advance the cause of gay marriage.

And see if this argument sounds familiar:

Polyamory is a fact. People are living in group relationships today. The question is not whether they will continue on in those relationships. The question is whether we will grant to them the same basic recognition we grant to other adults: that love makes marriage, and that the right to marry is exactly that, a right.

Read the whole article at Politico. And take a word of advice from G.K. Chesterton: If you can’t see the reason for a fence to exist, wait until you understand why it’s there before tearing it down.