"Once again, Sweden is showing us a possible future. The idea that we can and should abolish marriage and recognize multi-partner unions has its advocates in America, though they may seem too few to be bothered with. We ought not, however, mistake their chances for long-term success. Those radical advocates recognize something that even the moderate proponents of gay marriage overlook or deny: gay marriage changes the way that young people see and understand their social world. The slope from gay marriage to polyamory and ultimately to no marriage is not slippery by accident, but by design."

Gene Edward Veith:

"Civil unions would become a sort of 'marriage lite.' You could enter into them and take advantage of the legal benefits, but then leave them whenever you wanted. No messy divorces. No marital property laws. No alimony payments. No child support. All the benefits of marriage without any of the hassle.

Which raises the question, if you can get a civil union, why get married? Heterosexual couples in Europe and in Canada are already acting on this logic. They are registering for civil unions as a replacement for marriage. They live together, have kids, and raise them, just like any traditional family, but whenever they want to leave they can go their separate ways. Marriage lite drives out real marriage."

Mary Ann Glendon, Harvard University professor:

"Same-sex marriage will constitute a public, official endorsement of the following  extraordinary claims made by the Massachusetts judges in the Goodridge case: that marriage is mainly an arrangement for the benefit of adults; that children do not need both a mother and a father; and that alternative family forms are just as good as a husband and wife raising kids together. It would be tragic if, just when the country is beginning to take stock of the havoc those erroneous ideas have already wrought in the lives of American children, we should now freeze them into constitutional law. That philosophy of marriage, moreover, is what our children and grandchildren will be taught in school. They will be required to discuss marriage in those terms. Ordinary words like husband and wife will be replaced by partner and spouse. In marriage-preparation and sex-education classes, children will have to be taught about homosexual sex. Parents who complain will be branded as homophobes and their children will suffer.

Religious freedom, too, is at stake. As much as one may wish to live and let live, the experience in other countries reveals that once these arrangements become law, there will be no live-and-let-live policy for those who differ. Gay-marriage proponents use the language of openness, tolerance and diversity, yet one foreseeable effect of their success will be to usher in an era of intolerance and discrimination the likes of which we have rarely seen before. Every person and every religion that disagrees will be labeled as bigoted and openly discriminated against. The ax will fall most heavily on religious persons and groups that don't go along. Religious institutions will be hit with lawsuits if they refuse to compromise their principles."