Since Ronald Reagan, Republican Presidents (and Presidential nominees) have been committed to overturning Roe v. Wade, the Supreme Court’s abortion-rights landmark from 1973. But as the debates last weekend in New Hampshire suggested, the G.O.P. appears to have taken a more extreme step in terms of rolling back the Constitutional right to privacy.

Since the first time Mitt Romney ran for President, four years ago, he’s been on record reversing his previous support for abortion rights. However, when pressed by George Stephanopoulos in the debate Saturday night, Romney went beyond mere opposition to Roe. He said he thought Griswold v. Connecticut, the 1965 case that first made explicit the right to privacy, was also wrong. “I don’t believe they decided that correctly,” Romney said. In this, the front-runner was eagerly seconded by Rick Santorum, who said the Justices “created through a penumbra of rights a new right to privacy that was not in the Constitution.”

In Griswold, the Court ruled that a Connecticut law banning the sale of contraceptives, even to married couples, was unconstitutional. In the most famous passage from that opinion (which Santorum alluded to) Justice William O. Douglas said, “Specific guarantees in the Bill of Rights have penumbras, formed by emanations from those guarantees that help give them life and substance. Various guarantees create zones of privacy.” Later, Douglas said, “We deal with a right of privacy older than the Bill of Rights—older than our political parties, older than our school system.”

Roe has long been controversial, of course. But Griswold, largely, has not. For example, while John Roberts and Samuel Alito were cagey in their references to Roe in their confirmation testimony before the Senate Judiciary Committee, both of them readily embraced Griswold as a settled precedent of the Court. This is understandable. It is chilling to believe that the Constitution could allow a state to ban married couples from buying birth control. (A few years after Griswold, in a 1972 case called Eisenstadt v. Baird, the Court said states could not ban unmarried people from buying birth control, either.)

Because of cases like Griswold, Eisenstadt, and Roe, the right to privacy has long been associated with sexual liberty. But as Griswold and the right to privacy become newly controversial, it’s worth remembering that the right has deeply conservative roots. The two most important cases that Justice Douglas cited in his opinion were Pierce v. Society of Sisters, from 1925, and Meyer v. Nebraska, from 1923. Both cases grew out of the anti-foreigner sentiments that were rife in the United States during and after the First World War. In Pierce, Oregon had required all children to attend public schools; the law was plainly intended to eliminate parochial schools. In Meyer, Nebraska forbade the teaching of the German language anywhere in the state.

Both laws were and are plainly repellent, but it’s difficult to say precisely which provision of the Constitution they violated. The laws implicated freedom of speech and the free exercise of religion, as well as equal protection of the laws. Still, the Court had no trouble striking down both of the laws, even in a period of the Court’s history when the defense of civil liberties was not a high priority. Indeed, both decisions were written by Justice James McReynolds, who was himself a notorious reactionary and bigot. What McReynolds recognized (as have virtually all Justices since then) was that these laws violated a libertarian core that’s reflected in many provisions of the Constitution.

And that is what makes Romney and Santorum’s criticism of Griswold so troubling. Over the years the modern Republican Party has reflected both libertarian and authoritarian tendencies. Both survive, in a way. When it comes to taxes and regulation, the libertarian side of the party is ascendant. Even the rhetoric of compassionate conservatism has faded from view. But with regard to civil liberties, the G.O.P. has embraced state power with a vengeance. Whether it’s the rights of wartime detainees, or abortion rights, or the rights of gay people to marry (or to be free from discrimination), contemporary Republican leaders reflect clear moral disapproval. (Even Ron Paul, who is often described as a libertarian, is a fierce opponent of a woman’s right to choose abortion. And Rick Perry recently announced that he’s against a right to abortion even in cases of rape or incest.) Privacy is often described as “the right to be left alone,” but that’s not a value that seems terribly important in the G.O.P. right now.

The old cases of Pierce and Meyer show how important that right is. Though we may live in sex-obsessed times, these cases serve as useful reminders that an overbearing state can also assert itself in other ways. Republicans, and conservatives of all kinds, should be especially attuned to the possibility of governmental overreach. As Romney and Santorum illustrated last weekend, they’re not.

Photograph by Chip Somodevilla/Getty Images