Yul Brynner and Deborah Kerr in the film version of Rodgers and Hammerstein's "The King and I.” (AP)

When I find myself in times of trouble, Rodgers and Hammerstein come to me. I play the first notes of the opening song of “South Pacific” or “The King and I,” and I’m transported instantly back to my bedroom in East Brunswick, N.J., with the weird plaid wallpaper (thanks, Mom) and the wall mirror shaped like a pair of John Lennon’s glasses, where I am again 15 years old and listening to a show tune from the golden age on a scratchy 33 rpm cast album.

These musical cues by the famous Broadway songwriting team are frozen in time for me, a time of teenage credulity, of a kid trying to unlock the mysteries of adult achievement. They reflexively rekindle my innocence, my immature rapture in the discovery of something to believe in. Knowing that the musical is not a form that everyone considers a proving ground of genius — “Oklahoma!” may not be up there for you with “The Scarlet Letter” or “Blowin’ in the Wind” or “Waiting for Godot” or Monet’s water lilies or Beethoven’s Ninth Symphony — doesn’t matter a whit. In some incalculable way, these shows touch me more profoundly than do all those others combined.

Nicholas Rodriguez as Billy Bigelow and Betsy Morgan as Julie Jordan in "Carousel" at Arena Stage. (Tony Powell)

The powerful sentimental and intellectual attachments we forge at impressionable times, the ones that, as we get older, resist personal revision most strenuously, are the most potent examples of what I think of as nostalgia. And we are, certainly, as vigorously as ever, a nation of nostalgists, aided in this by technology and the ever more advanced tools of memory-jogging. We all have our essential reference points — and fortunately one of mine, Rodgers and Hammerstein’s “Carousel,” is next up at Washington’s Arena Stage. But they can also come in the form of a sonnet or a heavy-metal band, a Saturday cartoon series or a concerto. Or any combination of the above. As much as we claim to crave artful novelty in our diet, the culture feeds just as hungrily on the past — or rather, on your past and mine.

In an age of high anxiety — economic or political — we tend to reach into the cabinet of our comforts and scrounge for reminders of stabler periods. So now, it seems, is prime time for nostalgia. As a relatively popular presidency, and the most vulgar and corrosive national election of modern times, both wind down, a nation looks for reassuring signs — and often finds them in the rearview mirror.

Whether it is for theatergoers a frequent ride down memory lane, via jukebox musicals with songbooks by baby boomer artists; or for moviegoing audiences, reactivating again and again that soft spot for comic book figures like Superman or the X-Men; or for TV addicts waiting for the latest sequel to some cult hit of the ’80s or ’90s, the worlds of art, social media and popular entertainment are paved these days with touchstones. “Never miss a memory,” Facebook commands us, as it doubles down on nostalgia, transforming users into cogs in a vast, daily self-reflection machine, reprocessing forgotten experiences into “events” to be forever savored. (I’ve had more than one friend complain about a pet death or long-expired relationship Facebook awkwardly resurrected, in its cheerful, buttinsky “On-This-Day” way.) Costume meetups like Comic-Con are, in a fundamental sense, efforts to satisfy the modern craving for endless juvenile escape, a Perpetual Halloween, and the online explosion of another enthusiast’s delight — fan fiction — signals an urge to coexist nostalgically in the same space forever with the fictional object of one’s affections.

“Sebastian is in love with his own childhood,” is how one of the central characters is described in “Brideshead Revisited,” Evelyn Waugh’s sublime 1945 novel of Catholic aristocrats in England. How current an observation that still sounds. Sebastian Flyte is nostalgia personified: a scion of a storied family who strolls the lawns of Oxford carrying his teddy bear everywhere. The assessment of him, of course, by Sebastian’s father’s Italian consort, was not intended as a compliment. But does nostalgia, when applied to art, always have to carry a negative, hidebound connotation? There is as much in the term to suggest a warm, even revivifying homage — think of bare-shouldered Lady Gaga, gracefully crooning at the Oscars from the half-century-old “The Sound of Music” score — as there is of the faddishly retrograde.

The original company of the 1943 production of “Oklahoma,” starring, from left, Lee Dixon, Celeste Holm, Alfred Drake, Joan Roberts, Joseph Buloff and Betty Garde. (Bettmann/Getty Images)

Nostalgia, when expressed as respect for the aesthetic ideals of classicism, can even play a constructive civic role. Consider, for example, the successful campaign in New York to create a new Penn Station, inspired by the Beaux-Arts masterpiece demolished over protests in 1963. As architecture writer Jimmy Stamp noted at Smithsonianmag.com in 2013, photographs of the old station, built in 1910, instill nostalgia for a building that relatively few people today experienced firsthand. (The hideousness of the current structure that usurped the name certainly encourages this response.)

“The Penn Station we miss — even those of us who weren’t even a gleam in our father’s eye at the time of its demolition — is one that hadn’t existed for a long time,” Stamp wrote. “And yet, these photos create a longing.”

Shifts in attitude and taste over time may be so profound that figures or fashions that were once targets of abject derision may have their reputations restored, or their values longed for. The vulgarity and absence of substance in so much of our political discourse these days compelled the Economist to speak approvingly of the tenor, by comparison, of the State of the Union addresses of Richard M. Nixon: “One can’t help but feel wistful for an era,” the magazine wrote last year, “when a president’s ideas might’ve been debated on their merits, and when lawmakers took their job of making law seriously.”

As much as nostalgia seems a regressive phenomenon — a retreat to the consolation of what makes us feel unchallengeably secure — the fact is that the things we long for tell us something about who we are today. In the war-racked year of 1971, a transitional time in American life if there ever was one, the big hit on Broadway was a musical from 1925. “No, No, Nanette” was as mindless a piece of fluff as you can imagine, noteworthy mostly for the jaunty soft-shoe number, “Tea for Two.” Its robust success sent producers scrambling to the archives for other innocent musicals from another time that they could dust off and put on the boards.

What fads will get us through these times? I’ll think more about that, as I contemplate the upcoming Broadway revival of “The Glass Menagerie,” book my seats to the Stevie Nicks concert at Verizon Center, get ready to buy Christmas tickets to “Rogue One: A Star Wars Story” and do a search for the Netflix reboot of “Gilmore Girls.”