The first problem with the article is it displays a profound misunderstanding of what "deconstruction" means. Conservatives seem to think it means "destruction," when we deconstruct the meaning of words we destroy them. That is not what it means at all. Rather, deconstruction stems from the axiom that words have multiple meanings, both existent and potential, and that language games involve the elevation of certain meanings and the suppression of others. When we "deconstruct" a word, phrase, or idea, then, we examine why it is that a particular meaning (or meanings) have become privileged, while others have been subordinated.
Conservatives might respond that with multiple meanings that are always situational and contingent, language becomes utterly incoherent, so it's as if we destroyed the meanings. However, this isn't true, and Watson himself demonstrates how:
For Christians, in particular, marriage has meant the union of a man and woman. This is because it refers, among other things, to the unique, God-given capacity of man and woman to enter a covenantal relationship parallel to that between Christ and His church. It is a point of encounter between God and man. The rites of marriage are performed in the hope-with full knowledge that the reality sometimes does not live up to the hope-that each and every example of the sacramental relationship realizes its potential and purpose and therefore reflects the divine intention. The divine mind has an idea of human nature, and therefore human relationships, that does not and cannot change. Marriage, in short, is a word that describes something particular in the divinely created natural order, something that simply cannot be replicated in a same-sex relationship.
I am not Christian. Hence, this "meaning" of marriage is, in a tangible sense, utterly foreign to me. I cannot reach it. "A covenantal relationship between Christ and his church" is beyond my philosophical horizon. I do have my own, Jewish conception of marriage, which has both similarities and differences with the Christian form, but still is in the end a different ritual. And yet, despite this, I can somehow recognize the relationship described as a "marriage." Something allows me to transcend the particularities of my experience to understand the experiences of the other, without--and this is the important part--either disparaging my own experience or denying its meaning. I can do the same thing for homosexual marriages, even though, as a heterosexual, it too is completely "distant" in a tangible sense. The deconstructed idea of marriage doesn't destroy meanings, it affirms multiple meanings as valid based on context.
What's interesting is that we accept the presence of "multiple meanings" all the time, generally without question. A Christian marriage might require the parties to recognize their bonds under Christ. A Jewish marriage obviously doesn't have that facet, yet most Christians would still accept it as a valid marriage, even if the same act would not be a valid marriage amongst Christians. The reverse is true too, Jews recognize Christian marriages without a Ketubah as legitimate, even if it is required for Jews and would make for an invalid marriage if the parties were Jewish. One might argue that acceptance of uncertainty and multiple life-paths is a precondition to a pluralist society--if I am utterly convinced that my way is the one true way, then democratic deliberation becomes an unnecessary barrier to utopia. As Chantal Mouffe puts it:
To believe that a final resolution of conflicts is eventually possible...far from providing the necessary horizon of the democratic project, is something that puts it at risk. Indeed, such an illusion implicitly carries the desire for a reconciled society where pluralism would be superseded. When pluralist democracy is conceived in such a way, it becomes a self-refuting ideal because the very moment of its realization coincides with its disintegration.["Democracy and Pluralism: A Critique of the Rationalist Approach," 16 Cardozo L. Rev. 1533, 1544 (1995)]
Hence, so long as acceptance of the right of some communities (IE, churches, families) to include gay marriage under the umbrella of marriage doesn't disparage the rights of other communities to reject it, pluralism is achieved.
One could also recast the question as a matter of "essences." What are the essential attributes of marriage? This is to some degree a peculiar question, since again, people somehow affirm that a Ketubah is essential to a Jewish marriage but not to marriage abstractly. Beyond that, though, the question of "essences" is infinitely reductive. Is marriage "a union between a man and a women under Christ," or "a union between a man and a women" or "a union between two loving persons"? All definitions include some and exclude others. So we have three choices: we can draw the line arbitrarily, simply in line with whatever social stereotypes and preconceived prejudices we've inherited from our ancestors; we can draw the line as far out as possible, including everything but meaning nothing; or we can reject the need for line-drawing at all and recognize that there are no abstract essences, just the individual traits of particular relationships. I'd assert that the last option is preferable, preserving meaning while including the hitherto excluded. It also allows for some forms of social control--bestiality is not prohibited because it violates some "essence" but because it violates the notion of consent which is required to enter into contractual relationships.
From a legal perspective, Watson's case grows weaker still. One might indeed believe that preserving marriage as a bond between a man and a women (or a Christian man and women) is worth defending. Nothing in any legal decision has cast otherwise--every Christian church in the land, if it so chooses, can continue to define marriage as such. However, from the perspective of the state, such inter-denominational spats (even if, in this case, the denominational breakdown is predominantly religious versus secular) are not to be waded into. The one true meaning, if it even exists, is of no concern to it (indeed, setting that meaning up as inviolable is inherently anti-democratic, see Mouffe above). The state is a pragmatic body, it tries to achieve pragmatic goals. Those goals have to be within the recognized authority of the state. Playing dictionary is not one of those goals, the state is (for obvious reasons) not vested with the authority to tell us, under pain of legal sanction, the final meaning of diction. The definition of marriage, preserving the ability of man "to express the union of a man and woman," as Watson so hyperbolically puts it (as if language can only exist within the context of state mandates. I should hope our social traditions are not so fragile!), is not valid material for the government to play with. States can, however, do many things that have a secondary relationship to marriage--for example, it can look out for the well-being of children, or encourage stable relationships. In pursuing these goals though, the state must act with as fine a scalpel as possible. If the goal is aiding children, then the state should assign whatever benefits it deems appropriate to any family unit with children. It is not enough to say that most married heterosexual couples either have or have the capacity to have children and most homosexual couples don't, because that is needlessly exclusive and their is a more precise mechanism available. The same thing applies to fostering safe and stable relations, whatever the state decides is necessary to achieve that goal, it must make available to any partnering that has the capacity of being safe and stable. The formulation may be laid down as such: When seeking to achieve a legitimate political end, the state cannot adopt a more exclusive policy in cases where it could just as easily adopt a more inclusive one without substantially changing the nature of the objective.
Watson's argument stems from a flawed premise of what deconstructionalism means, proceeds to defend arbitrary essences which do not exist, and then concludes by placing the duty to defend the whole enterprise at the foot of a state whom conservatives used to be wary of vesting so much power in. I would think that the prospect of Orwellian newspeak grows greater if we become dependent on government to define our meanings for us, rather than forming vibrant communities of our own in which we can pursue our version of nature, essence, and the meaning of life.