It’s the start of summer in the northern hemisphere, and thus the season for a million stories about air travel: the record numbers of people moving by air, the delays, the guy who stripped nude to protest the TSA, the tips on how to travel with a terrier or which on-board wine to pair with your foil-wrapped chicken marsala.

But precious little is written about airports themselves. They’re such fascinating spaces. It’s easy not to notice that, not even to think about them, because they’re fundamentally so similar to each other. We tend to notice difference. The air when we step off the plane in Los Angeles or Beijing, the architecture in Stockholm or Morocco. But it’s the sameness of airports that’s precisely their intrigue.

A week ago, I flew from Seattle to Washington, D.C. A week before that, I’d flown from South Africa to America, and except for their lengths I could not tell the two trips apart. The rhythms of the journey, the lighting, the behavior of the flight attendants and desk clerks, the food — it was all the same. While roads and trains retain a faint aura of national distinctiveness — the traffic in Kenya makes driving more like traveling by turtle-back; the drivers in the mountainous Republic of Georgia are so wild they warrant a note in every guidebook — the experience of flying is virtually identical in Turkey, in Britain, in Uruguay. In the duty-free shop in Congo they stock the same whiskies and Toblerones they have in California, and the security agents, using Israeli scanners, seem to have assimilated their distinctively curt, bemused manner from TSA agents on TV.

I’ve spent the last half-dozen years traveling, and I’ve noticed over time that downtowns all over the world more and more resemble departure lounges. In his novel “The Moor’s Last Sigh,” Salman Rushdie describes the aura of one of these air-terminal-like strips at the center of a Spanish city: “Gucci, Hermès, Aquascutum, Cardin … [and] eating-places ranging from Scandinavian-meatball vendors to a Stars-and-Stripes-liveried Chicago Rib Shack.” Every store glows, like the sunrise- and sunset-lessness of the airport.

Have airports become more like our increasingly homogeneous elite urban spaces, or did the causal chain go the other way around: Are our cities becoming more like our airports? Even hipster culture increasingly feels the same everywhere. In South Africa, where I live, craft breweries indistinguishable from those in Seattle are popping up all over. The only distinctive thing I’ve found is that, in a culture where children are sometimes named after interesting events in the parents’ life or popular commercial products, I’ve met two babies named after favorite brews.

I suspect sometimes the causal relationship is the latter. Airport culture inspires our wider elite culture. It’s a paradox: We built airports to access irregularity, the differences in different parts of the world. But air travel, slowly but steadily, helps make elite life the same everywhere, or mirrors its growing sameness. And the character of our airports, often lamented, reflects the strange, culture-bleaching outcome of our will to reach places of real difference in the world, of our exotic dreams.