In some ways, the prediction came true. Rates of divorce, cohabitation before marriage and illegitimate births rose sharply in the years after 1968. The percentages of children living with two parents fell sharply. The "Hair" version of history -- hundreds of years of oppression followed by a sudden trend toward evermore liberation -- seemed plausible, even persuasive.
But history is not unidirectional. Trends get reversed or arrested sooner or later. Behaviors that at first seem modern and refreshing come to seem antique and old-fashioned. People adjust to new experiences just as they adjusted to old.
Today, several widely unanticipated trends -- certainly unanticipated by me -- suggest that America is in some significant respects entering a new Victorian Era. Some may regard that as regrettable, others as welcome, still others as a mixture of good news and bad news. But it's certainly news, especially to the aging baby boomers who expected the Age of Aquarius to continue indefinitely.
One such trend is the sharp decline in teen sexual activity. A Center for Disease Control survey showed that less than half of teenagers over 14 in 2013 have engaged in sexual intercourse, a sharp decline from 1988 -- and the decline is sharper among males than females.
Commentators are puzzled as to why this has been happening. Sexual appetites have surely not diminished and popular culture has hardly encouraged abstinence. The trend started well before teens got hold of smartphones or received HPV vaccines.
An accompanying trend is a sharp decline in births to teenage mothers. Increased use of contraceptives, including morning-after pills, may explain some of this. But abortion doesn't: the number of abortions has been declining since the 1980s.
Conservative millennial author Ben Domenech sees these trends as a "triumph of soft conservatism over time," but also as "another aspect of modern risk aversion." That latter trend is also apparent in the decline in unsupervised play for children and removal of jungle gyms and slides from playgrounds.
A tendency to risk aversion also helps explain the movement against the supposed plague of sexual assaults in colleges and universities, with administrators running kangaroo courts in which the accused (almost always men) are assumed guilty and denied due-process rights. This has been carried, as my Washington Examiner colleague Ashe Schow has documented, to ridiculous extremes.
But one can also see it as an updated version of the college rules against male-female sexual contact that were being dismantled as "Hair" was premiering on Broadway. Students, headed to Aquarius then, are subjected to quasi-Victorian restrictions now.
California and New York legislators have chimed in with "yes means yes" statutes applicable to students (but not other adults). The American Law Institute is considering a similar approach, which Judith Shulevitz in The New York Times called "the criminalization of what we think of as ordinary sex."
The 1960s saw a sharp decline in birth rates -- the end of the baby boom -- especially among the highly educated and affluent. But as Charles Murray documented in his 2012 book "Coming Apart," the highly educated abandoned Aquarian rates of divorce and extramarital sex in the 1980s, while these rates have remained high among the less educated.
Now there's been a trend since the 1990s toward higher birth rates at relatively late ages, and lower childlessness among highly educated women. And more women with higher educations are deciding the stay at home with children and pause their careers. Queen Victoria, a teen bride and mother of nine (the last at age 37), might approve.
Even the legalization and vastly increased approval of same-sex marriage has a Victorian aspect. The early same-sex marriage advocates Andrew Sullivan and Jonathan Rauch argued that marriage would domesticate homosexuals. There's logic to that -- marriage inevitably includes elements of restriction and restraint -- and we will see how it works out.
The most recent Washington Post-ABC News poll shows that 63 percent of Americans are uncomfortable with the nation's direction on social issues, even though 52 percent supported the Supreme Court's 5-4 ruling overturning bans on same-sex marriage. Perhaps that apparent ambivalence is an understandable response as America moves in some significant ways from the Age of Aquarius to a new Victorian Era.