Third, polygamy and more. Once it is established that two men have the right to marry, it will be impossible to deny that same right to others. If marriage can be redefined as any two men or two women in love, what rational principle precludes extending that logic to polygamy—or any other combination of emotionally attached men, women, or children? If emotional attachment is the only standard by which we judge fitness to marry, then no sexual arrangement is off the table.

Family law theorists are pushing in this direction. Kurtz cites, among many examples, University of Michigan law professor David Chambers, who thinks homosexual marriage will help to soften society to other alternatives. “By ceasing to conceive of marriage as a partnership composed of one person of each sex,” Chambers wrote, “the state may become more receptive to units of three or more.” The ACLU, which has announced its support for removing laws against polygamy, will be glad to help.

Fourth, say good-bye to free speech. It’s speak now or be forced to forever hold your peace if same-sex marriage is legalized nationwide. That sounds extreme, but the push to stifle dissent is already evident in Canada, where homosexual marriage became legal last year. In April, the Canadian parliament passed a measure criminalizing “hate speech” against homosexuals. The law has a religious exemption, but that is little comfort since a Saskatchewan court has found the Bible to be hate literature. It upheld in 2003 a fine against a man who placed a newspaper ad with Bible verses on homosexuality. Also last year, Swedish authorities arrested a pastor for “hate speech against homosexuals” after he preached a sermon with biblical references to homosexuality.

Take your pick. The short answer or the long answer. God and nature or a panoply of bad outcomes that will follow the state’s stamp of approval on same-sex marriage. Forty years after the sexual revolution promised “free love” but brought divorce, illegitimacy, STDs, fatherlessness, and abortion, the last thing our nation needs is one more misguided social experiment.

That is why Congress must pass the Federal Marriage Amendment this year to protect marriage from activist courts eager to impose, against our will, a radical redefinition of marriage in America. The House and Senate must act now to protect what the Supreme Court once called the “sure foundation of all that is stable and noble in our civilization.”

D. James Kennedy, Ph.D., is Senior Minister of Coral Ridge Presbyterian Church and President of Coral Ridge Ministries. He is the coauthor with Jerry Newcombe of What’s Wrong With Same Sex Marriage?, available from Crossway Books in August.