Karen Dunak is associate professor of history at Muskingum University in New Concord, Ohio. She is the author of "As Long As We Both Shall Love: The White Wedding in Postwar America."

Serena Williams’s baby shower embraced a cultural nostalgia for the 1950s that sanitizes the real history of the time and feeds the effort to revive the era’s politics. (AP Photo/Ben Curtis, File)

Serena Williams has excelled at playing the celebrity pregnancy game. When she released pictures of her baby bump, a) she looked good; b) those who grasped her pregnancy timeline immediately realized that she’d won the Australian Open while pregnant; and c) it just happened to be her disgraced rival Maria Sharapova’s birthday.

Game, set, match: Serena.

So it’s not surprising that pictures from Serena’s 1950s-themed baby shower took the world of social media by storm. They are chock-full of other celebs: La La Anthony, Eva Longoria, Kelly Rowland, and of course, sister Venus. Clad in the Fifties-era vintage style and posing with props on hand at Nick’s 50’s Diner in West Palm Beach, Fla., the women looked incredible and clearly had a great time.

There is something to be said for them appropriating an era, laying claim to the enjoyment of the lighter side of a time when many women, and especially women of color, experienced incredible discrimination and unbearable hardship. And in embracing the aesthetic of the 1950s while clearly living as modern, empowered women, they are making an unspoken but marked point about how things have changed.

Yet by glorifying 1950s culture in the political climate in which we live, these women, who assuredly would not want to return to Jim Crow-era Florida, unwittingly reinforced a dangerous nostalgia that obscures the era’s harsh historical realities. Although the 1950s were great for white, heterosexual Americans, for people of color and sexual minorities it was a time of racial violence and pervasive sexism and bigotry.

But Williams’s baby shower does not just promote a romanticized history of the 1950s. This very nostalgia itself has served as a cultural justification for restoring the politics and hierarchies of the era. One cannot venerate the culture of poodle skirts and sock hops without furthering the cause of those who want to Make America Great Again.

President Trump attracted fans with this slogan because a segment of the population has long imagined a triumphant return to 1950s America, an America not yet irrevocably changed by the New Left, counterculture and the civil rights, women’s liberation and gay liberation movements of the 1960s and 1970s.

An America where “men were men” and “women were women.” An America where those men faced economic competition only among their own kind (that is, other white men), and thus enjoyed a certain kind of affirmative action. An America where those men’s breadwinner status cemented them as unquestioned heads of their households. A prosperous America, manufacturing the consumer goods citizens had done without as they had endured economic depression and wartime scarcity. A disciplined America, without the “bloated government” so despised by followers of Trump.

Nostalgia for the era emerged in the early 1970s and manifested itself through a yearning for 1950s culture: college campus visits by Buffalo Bob and Howdy Doody (evidence that baby boomers would generate a massive nostalgia market in decades to come); a renewed hula hoop craze; and pop culture paeans to the era such as American Graffiti, Happy Days and Grease. In 1971, the New York Times published a story with the headline “Students Revive Good Old 1950’s” and noted that “today’s college student missed out on the college life of panty raids, clubs, and big weekends. They had politics instead … some students may feel they missed something.”

The rise in this cultural craving to return to the 1950s came from people dismayed by the political changes roiling society and the movements laboring to reimagine its cultural mores and hierarchies. Then, as now, the nostalgia came from those who had long been at the top of the pyramid — socially, economically, politically — and found themselves no longer certain about the world or their place in it. The disorienting effects of the Vietnam War, deindustrialization, Watergate, the sexual revolution, the energy crisis, women demanding equality and persistent racial unrest only served to make an idealized image of the fifties that much more desirable.

This cultural nostalgia, supported by the era’s popular culture and media narratives, fed an emergent political nostalgia. Conservatives such as Ronald Reagan employed sanitized celebrations of the 1950s to stoke this wistfulness and build support for their plans to return America to a better, more triumphant time before white Americans sensed theirs was a nation in decline.

In 1974, Reagan, then governor of California, spoke of the United States as a “city on a hill,” and recalled that in his youth “none of us knew that we even had a racial problem.” Thanks to “editorializing and campaigning” by people like him, he claimed, things began to change. He gave no hint of the dogged determination of civil rights activists or the violent resistance they faced. He belittled the Great Society, rattling off numbers of government programs to demonstrate government bloat, but giving no indication of the good they had done.

In 1980, with an eye to the “good old days,” Reagan, like Trump, campaigned on a promise to Make America Great Again. He aimed to make good on this pledge through deregulation, cuts to the social welfare state, a military buildup and efforts to undermine gains made by the social movements of the previous two decades. Many of those prospering thanks to these policies were Americans who had benefited from 1950s-style social, political and economic hierarchies. And even for those not benefiting, the appeal of triumphant rhetoric, of a great nation in which they could believe and be proud, has held strong.

All of this highlights the question: For whom were these good old days so good? The cultural nostalgia of the 1970s, one echoed in Serena Williams’s baby shower, was for a version of 1950s life enjoyed only by a certain privileged segment of the population — specifically, white Americans who embraced traditional gender roles and definitions of the family. The ways in which that privilege has been jealously guarded should give us pause whenever we catch a whiff of 1950s revivalism.

It can be great fun to indulge in the culture of the past, and some likely would suggest that such fun is harmless. But idealizing the culture of this earlier era, especially when done by popular celebrities, has troubling underpinnings. It legitimizes the politics and the hierarchy of the period and fuels a contemporary quest to restore them, a dangerous proposition for the many groups who found themselves shut out from those avenues of power. For that population, a return to the past would be anything but great.