As my 3-year-old niece likes to say: Calm down, everyone! On June 26, in Lawrence v. Texas, the Supreme Court ruled state sodomy laws unconstitutional. Only a few days earlier, Canada had effectively legalized same-sex marriage, and there were rumblings that the Massachusetts Supreme Court might do the same in that state. So, when the U.S. Supreme Court planted itself on the side of gay rights, something like hysteria ensued in the conservative commentariat.

In an inflammatory dissent, Justice Antonin Scalia accused the Court of undercutting not just sodomy laws but all morals legislation, including the ban on same-sex marriage. The Family Research Council, a prominent anti-gay lobby, said that Lawrence would cover not only choice of sexual partner but "choice of marital partner as well."

Within a few days, conservatives were saying not just that same-sex marriage might happen but that it was practically a done deal. Gay marriage, wrote Ramesh Ponnuru in National Review, is "not quite inevitable." In the same magazine's online edition, Maggie Gallagher, a conservative columnist, gave notice of the apocalypse. "We are poised to lose the gay-marriage battle badly," she said. "It means losing the marriage debate. It means losing limited government. It means losing American civilization."

As Scalia said in his Lawrence dissent: Do not believe it.

I support gay marriage. It would be good for homosexuals, good for heterosexuals, and good for the institution of marriage—especially as compared with the alternative, which is the proliferation of "marriage lite" arrangements. If I could wave a magic wand and summon same-sex marriage into existence, I would do it. But I do not have a magic wand, and neither does the Supreme Court. Herewith, a reality check.

The Supreme Court has not undercut all morals legislation. All it said is that if a legislature wants to intrude in a fundamental way on a core right, lawmakers have to give at least one better reason than just, "Because we disapprove."

All laws are built on morality, and should be. Murder and rape are illegal because they are wrong. But murder and rape are illegal not only because they are wrong. They violate the rights of others and cause personal and social harm. By contrast, there are lots of things I could do that are immoral but not illegal.

Texas, in Lawrence, offered no plausible rationale for arresting gay people other than the fact that the Legislature disapproved of gay sex. Well, West Hollywood, a heavily gay jurisdiction, could not arrest people for having heterosexual intercourse merely because a majority of the city council disapproved of heterosexual intercourse.

Gambling, prostitution, and pornography are economic transactions, with all kinds of implications for neighborhoods and communities. Incest opens the door to sexual predation within families. Polygamy undermines marriage by leaving less-desirable men short of partners. These days, criminal laws based solely on moral disapprobation are few. Sodomy laws happen to be among them.

Limits on the government's power to ban anything that it happens to deem immoral are not new. They go all the way back to John Locke. There are many ways to express disapproval without threatening people with arrest. The Supreme Court merely told Texas to go find one of them.

The Court did not create a sweeping new right to privacy or anything else. All it said was, if the law already gives you the right to have an abortion in a hospital, then it certainly gives you the right to have sex in your own home.

In the 1986 case of Bowers v. Hardwick, the Court famously said that any claim of a constitutional right to sodomy must be "facetious." But that ruling, inasmuch as it allowed the arrest of people just for having sex at home, was at odds with more than 20 years of precedent. In Griswold v. Connecticut (1965), the Court said that banning contraception violated "the right of marital privacy." In Eisenstadt v. Baird (1972), it extended the same privacy rights to unmarried people. By letting single people use contraception, the Court gave them a constitutional right to have non-procreative sex—which is exactly what Texas arrested John Geddes Lawrence and Tyron Garner for doing. Roe v. Wade, legalizing abortion, extended the privacy right still further.

Note the Court's language in Lawrence: "The Texas statute furthers no legitimate state interest which can justify its intrusion into the personal and private life of the individual" (italics added). Texas can restrict private conduct with a good reason, and it can unreasonably restrict conduct that isn't private. It just can't unreasonably restrict private conduct. The Court is not creating a new right; it is merely saying it wasn't kidding about an old one.

The sodomy ruling won't lead to same-sex marriage. Despite what Scalia says, it's hard to see how it could.

The whole point of Lawrence is to curtail an unwarranted state intrusion into private conduct. You don't need a blood test and a government license to have sex at home. By contrast, the whole point of state-sanctioned marriage is that it is public. I can hold a private commitment ceremony without any fear of arrest, but of course what I won't have is a marriage license.

No doubt someone will bring a lawsuit demanding that the Supreme Court find a constitutional right for gay people, like straight people, to wed a partner of their choice. But this would not be a privacy suit. It would be an equal-protection suit, saying that states should not discriminate in the granting of marriage licenses.

Discrimination law is not like privacy law. Because gays are not what federal law calls a "suspect class," the government is perfectly free to discriminate against them if it has a "rational basis" for doing so. After Lawrence, a state can no longer cite the illegality of gay sex as its reason to forbid gay marriage. But the "rational basis" standard is a very permissive one—almost any public-policy rationale will do—and states will not be short of arguments as to why same-sex marriage does not serve the public interest.

Is it possible that a conservative Supreme Court might invade the inner sanctum of states' rights (marriage law has been within the states' purview since colonial times) in order to ram same-sex marriage down the throat of an unwilling public? Yes, and monkeys might fly out of my posterior.

In any case, a lawsuit challenging marriage-license discrimination would be decided on its own merits and under its own branch of the law. The sodomy case would have little or nothing to do with it.

Massachusetts can't impose same-sex marriage on all of America. For that matter, neither can Canada.

No state is obliged to recognize any foreign marriage. The marriage of an 11-year-old Pakistani girl will cut no ice in Michigan. Nor is any state obliged to recognize out-of-state marriages.

It is true that the Constitution's "full faith and credit" clause requires states to recognize each other's laws and judgments. "However," notes Dale Carpenter, a constitutional law professor at the University of Minnesota, "the full faith and credit clause has never been interpreted to mean that every state must recognize every marriage performed in every other state. Every state reserves the right to refuse to recognize a marriage performed in another state if that marriage would violate the state's public policy."

This "public-policy exception" is well established. Another lawyer I consulted said, "I have not found a single case where a federal court has forced another state to recognize a marriage where the state asserts that said marriage would violate the public policy of the state." Moreover, he notes that many states have "evasion statutes" that forbid going out of state to enter into a marriage that would be prohibited in state. "None of these provisions," he said, "have been struck down under full faith and credit." Moreover, Congress has passed a federal law reiterating that no state need recognize an out-of-state gay marriage.

So, might a conservative Supreme Court overturn all of those precedents and laws and trample on states' rights in order to impose Massachusetts's same-sex marriages on 49 other states? See "monkeys flying out of my posterior," above.

Stirring up a gay-marriage panic serves the interests of activists who support a federal constitutional amendment banning same-sex marriage. But decisions made in a panic are seldom wise. With its federalist structure, the United States is uniquely positioned to settle gay marriage the right way: at the state level. Without either a national ban or a national mandate, each state is free to go its own way, acting as a distinct moral community. Domestic law is best left to the people who are, literally, closest to home.

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