In this particular battle in our nation’s “culture wars,” the two opposing sides are fighting about the understanding of man and his relationship to truth and reality.

One side — and today “gay marriage” is its poster child — holds that anyone can essentially create his or her own reality. This side holds for a radical autonomy by which truth is determined not by the nature of things but by one’s own individual will.

The other side holds men and women are not self-creators but creatures. Truth is not constructed, but received and thus must reflect the reality of things. Or, as the Book of Genesis says: “Male and female, He (God) created them.” (Genesis 1:27).

The former’s position, like that of the secular utopias of the 20th century, is a recipe for tyranny; the latter’s position promises a freedom that is only achievable through adherence to objective truth which we do not, and could never, invent.

In seeking to redefine the legal definition of marriage to include same sex unions, President Obama and other proponents of “gay marriage,” in effect, are imposing their views and lifestyle on the larger populace. Once legal, the state’s coercive power will punish those who refuse to embrace gay marriages.

For example, public officials — regardless of their views on the rightness or wrongness of homosexual acts — will be obliged to officiate at same sex “weddings,” and public schools will be required to teach their acceptability to children whether parents concur or not.

Even First Amendment freedoms will not be protected from assault.

Marriage has been primarily about the raising of children (who seem to be hardwired to be best raised by a father and a mother who are married to each other). Society has a legitimate interest in favoring such traditional marriages as a way of investing in the future of society by providing for the human flourishing of upcoming generations.

Same sex “marriage” — if allowed to prevail in law — will result in the devaluation of all marriages with terrible consequences to society. That marriage is a lifelong union between a man and a woman is certainly part of Catholic teaching — in fact, in our teaching, this union is seen as a covenant and is a sacrament.

However, marriage as a union between a man and a woman for the sake of family is not a product of religious sectarianism. Nor is marriage a creation of the state. It is founded in nature itself.

Marriage understood as a union between one man and one woman as an institution precedes church and state — if not a creation of church or state, neither has any authority to change the nature of marriage.

The common good demands that the understanding of marriage as a union between one man and one woman not be lost.

Thomas Wenski is archbishop of Miami.