Liberals and leftists have generally sought to put the results of the 2016 presidential race in one of two historical contexts. Some have cast the ascendance of a man who essentially built his political career on the racist claim that his predecessor was not a natural-born citizen as a blip in American history, a short setback on the road to greater equality and justice. Others have seen the event as part of a larger pattern: The history of struggles for freedom in America has been one of constant backlash, a series of hard-won victories followed by equally hard-fought defeats.

Sex and the Constitution, a new book by the legal scholar Geoffrey R. Stone that charts the laws governing sexual behavior and expression from the ancient world to present-day America, provides ample evidence for this latter view of the election. The book, which pays special attention to laws concerning contraception, abortion, obscene speech, and gay and lesbian sexual activity, is a story not of inexorable progress toward greater freedom, but rather a different kind of narrative, in which the laws and conventions around sex have moved from more to less permissive and back again many times over. 

Take contraception. Common in ancient Greece, it was denounced in the fifth century by Augustine, who pioneered the view that sex is permissible only for the purposes of procreation. Medieval “penitentials”—­written religious guides that helped priests hear confessions and assign penance—“banned married couples from engaging in sex during the wife’s menstrual period, during pregnancy, during the daylight hours, while they were naked, in any position other than the missionary position, in church, on Sundays, and on holy days.” As Stone observes, this “covered most of the year.”

Such strictures relaxed with the arrival of the Enlightenment, and by the 1860s, condoms, diaphragms, and IUDs were widely advertised in the United States. The birth rate dropped significantly between 1800 and 1900, indicating that couples were increasingly practicing birth control. But the Second Great Awakening brought a renewed religious zeal to the country and, with it, new restrictions on sexual behavior. The federal Comstock Act of 1873 made it a crime to send contraceptives or instructions for their use through the mail, and numerous “little Comstock” acts introduced similar restrictions in the states. The laws’ namesake, the anti-obscenity crusader Anthony Comstock, believed that birth control encouraged immorality because, as Stone writes, it “reduce[d] the risk that individuals who engage in premarital sex, extramarital sex, or prostitution will suffer the consequences of venereal disease or unwanted pregnancy.”

While the majority of Americans supported the legalization of birth control by the 1930s, pressure from the Catholic Church kept the Comstock acts on the books and put contraceptives out of reach for many, especially poor women. In 1961, Estelle Griswold and Charles Lee Buxton opened a birth-control clinic in New Haven in defiance of Connecticut’s especially restrictive laws. They were arrested, and their case went to the Supreme Court, which decided in Griswold v. Connecticut that the state law was unconstitutional because it infringed on the privacy rights of married couples. In 1972, this decision was expanded when the Court ruled in Eisenstadt v. Baird that the Constitution didn’t permit states to treat married and unmarried couples differently with respect to contraceptive laws. In effect, the ruling defined a constitutional right to use birth control. And again we arrived at a moment of greater sexual freedom after a long dark age, but one whose laws and customs concerning sex were not that different from those of the classical world.

Stone’s history stops short of the debates over funding for Planned Parenthood and the Affordable Care Act’s requirement to cover contraception, but both are now under threat, and it’s easy to imagine—especially in our current political moment—a return to the conservatism of the 1930s, when access to contraception was a privilege largely reserved for women above a certain income bracket and the laws were used to constrict sexual “permissiveness.”

By charting the legal and cultural history of sexual practices and reproduction, Sex and the Constitution makes clear that advocates of reproductive rights and sexual equality can’t expect the passage of time to do the work for them. Our laws governing sex have almost always been shaped by those fighting for greater control over their own sexual behavior and expression, and Stone’s book is ultimately a testament to the power of individual bravery and collective action. What we realize upon concluding this book is that every triumph of social progress can be rolled back. The work of equality is never completed, and this is true not only in the field of sex but also in immigration, voting, fair housing, and many other areas of civil and human rights.

One of the achievements of Sex and the Constitution is the way that, despite its framing as a work of legal history, it focuses so much on the work of activism that helps make law. Estelle Griswold is just one of the many activists Stone cites who advanced the causes of reproductive and sexual freedom at great personal risk to themselves. He also spends considerable time discussing Heather Booth, who founded the Jane Collective, an abortion-referral service that helped more than 11,000 women in Chicago obtain safe, affordable abortions when the procedure was still illegal, as well as earlier figures like Margaret Sanger and her sister Ethel Byrne, who were jailed for operating a birth-control clinic in Brooklyn, and Ida Craddock, whose sex manuals mentioned contraception and who committed suicide in 1902 after repeated prosecution under the Comstock Act. “Perhaps it may be that in my death more than in my life,” Craddock wrote in a public letter, “the American people may be shocked into investigating the dreadful state of affairs which permits that unctuous sexual hypocrite, Anthony Comstock, to wax fat and arrogant, and to trample upon the liberties of the people.” 

Stone’s emphasis on individual and collective activism is a reminder that in the history of sex and constitutional law, social and political forces have been at least as influential as the Constitution itself. The framers, living at a time when no state banned obscenity, contraception, or abortion before quickening, and when laws against same-sex intercourse were almost never enforced, probably could not have imagined the kinds of debates over sex that would rage several centuries later. Whatever the case, they never included any guarantee of sexual freedom in the Constitution, and as a result, they left the defense of sexual autonomy to ordinary citizens. 

Some of the most inspiring portions of Stone’s book focus not on reproductive rights, but on the struggles of gay men and women to gain rights and recognition in a homophobic society. In 1951, a group of gay activists founded the Mattachine Society to promote “homosexual emancipation” and to foster a sense of self-worth. Many members, fearful of arrest, used false identities at meetings. The Daughters of Bilitis, a lesbian advocacy group, emerged shortly after Mattachine and began publishing the journal Ladder in 1956. “In the 1950s,” Stone writes, “it took considerable courage not only to publish such magazines, but even to subscribe to or read them.” When police raided the Stonewall Inn in 1969, LGBT and queer patrons faced down the officers, throwing rocks, lighting fires, and singing, “We are the Stonewall girls, we wear our hair in curls, we wear no underwear, we show our pubic hair.” Stone quotes the transgender activist Sylvia Rivera: “It was one of the greatest moments in my life.” 

Much of this new sense of agency was channeled to great effect during the AIDS epidemic in the 1980s and early ’90s. Frustrated with the federal government’s slow and belated response to the crisis, over a thousand protesters from the group ACT UP (the AIDS Coalition to Unleash Power) demonstrated outside the Food and Drug Administration’s headquarters in 1988, chanting, “We die. They do nothing.” Two hundred people were arrested, but the FDA began expediting the development of AIDS drugs. 

As with much activism in the United States, one of the most lasting achievements of these campaigns has been their influence on public opinion, which led to new interpretations of the law. In his opinion in Lawrence v. Texas, which struck down that state’s law against same-sex intercourse, Justice An­thony Kennedy cited “an emerging awareness that liberty gives substantial protection to adult persons in deciding how to conduct their private lives in matters pertaining to sex.” That awareness emerged because gay and lesbian activists publicly agitated for their rights, just as reproductive-rights and sexual-liberation activists had done in the past. 

The stories of ACT UP, the Jane Collective, and others should stiffen the spines and lift the hearts of Americans concerned about the future of the country under the current administration, but uncertain about turning their concern into action. As Sex and the Constitution shows, Americans providing services, coming together in support and solidarity, and engaging in public protest have been able to help others survive when the government restricted their rights, and have been instrumental in getting such restrictions overturned. While framed as a history concerned primarily with the Constitution and legal norms, Stone’s book is also a useful blueprint for many activists today.

There are some areas, however, that the author neglects. Though he discusses in detail the attitudes and laws governing sex outside of marriage, he doesn’t deal with sexual assault or rape within marriage, which remained legal in most states until the 1970s. In several states, exemptions allowing men to rape their wives were struck down in court because they were judged to violate the 14th Amendment by treating married people differently from the unmarried. This is essentially the same justification that the Supreme Court used in Eisenstadt v. Baird to strike down a Massachusetts law prohibiting the distribution of contraceptives to unmarried people. Given efforts in recent years to hold universities and other institutions legally accountable for failing to prevent or punish sexual assault, Stone’s keen analysis on this issue would have been especially welcome. 

Stone is also relatively silent on racial discrimination and its effects on freedom of sexual behavior and expression. He mentions Loving v. Virginia, in which the Supreme Court struck down the state’s law against interracial marriage, as one of the cases cited in Justice Harry Blackmun’s opinion in Roe v. Wade. But he doesn’t explore the long history of laws against interracial marriage or sex in colonial America and the United States, or the repeated efforts, as recently as 1928, to amend the Constitution to prohibit interracial marriage. Nor does he address racial discrepancies in access to contraception or abortion, or in prosecutions for obscenity. While Stone mentions Buck v. Bell, in which the Supreme Court ruled that forced sterilization didn’t violate the Constitution, he doesn’t discuss the consequences of that decision for countless black and Native Americans who were forcibly sterilized after being falsely diagnosed as “feeble-minded,” a practice that lasted in some places into the 1970s.

Sex and the Constitution also doesn’t address the consequences of slavery, segregation, and racism for the sexual freedom of black Americans. While focusing on the laws and mores governing the sexual behavior of white residents in the colonies and in antebellum America in relative detail, Stone performs no such examination of the very different set of laws and mores that applied to enslaved people, who were often subject to forced reproduction, forced marriage, forced separation, and sexual assault, all with no legal recourse, since they were treated as nonpersons under the law. 

The framers chose to enshrine slavery in the Constitution, in the three-fifths compromise and elsewhere, and the denial of rights—including sexual and reproductive rights—to enslaved people was very much a constitutional issue. This denial and its effects on American law and politics, many feel to this day, are central to the larger historical argument at the heart of Stone’s project in Sex and the Constitution, and so it is unfortunate that he fails to include them. 

Despite these shortcomings, Stone’s book remains a powerful reminder that history doesn’t always progress as we might wish—and that it takes years of collective action and public agitation to transform American society. In a 2013 review of Tony Judt’s Postwar, Ta-Nehisi Coates wrote, “I don’t believe the arc of the universe bends towards justice. I think that those of us who reject divinity, who understand that there is no order, there is no arc…will understand that the only work that will matter, will be the work done by us.” Sex and the Constitution may not honor the work of all of the Americans who have fought for sexual and reproductive freedom. But it does offer an implicit refutation of the idea that if we just wait, our country will right itself on its own.